This was the third of the three names of a Roman citizen. They could be quite solemn and reflect public success but were often witty and even insulting. They could be passed on to a man's sons and daughters. If a man had been adopted, he would take the name of his adoptive father and a cognomen derived from the gens he had been born into. The Emperor Augustus was born an Octavius and took the cognomen Octavianus when he was adopted by his uncle, Gaius Julius Caesar. Freed slaves took the praenomen and nomen of their former master with their own original name as a cognomen.
| Abercius | Abito | Acacius | Acaunus | Acilianus | Adauctus |
| Adepphius | Adjutor | Adranos | Adventus | Aeacus | Aebutus |
| Aelianus | Aemilianus | Afer | Agapitus | Agatopus | Agelastus |
| Agorix | Agricola | Agrippa | Agustalis | Ahala | Albinius |
| Albinus | Albucius | Alethius | Aloysius | Aluredes | Alypius |
| Amandus | Amantius | Ambrosius | Ammausius | Ammianus | Amor |
| Amphion | Ampliatus | Ancus | Angelus | Annaeus | Antistianus |
| Antyllus | Anullinus | Apelles | Apellinus | Aper | Apollonarius |
| Aponius | Apuleius | Aquila | Aquilius | Aquillius | Aratus |
| Arcavius | Archarius | Arius | Armiger | Arpagius | Arrianus |
| Arruntius | Aruns | Arvina | Asclepiodotus | Asellio | Asiagenes |
| Asina | Asprenas | Asprenus | Assanius | Athanasius | Audaios |
| Audens | Augendus | Augurinus | Augurius | Augustales | Augustalis |
| Augustanus | Augustus | Auila | Aurelianus | Aurelius | Ausonius |
| Auspex | Auxentius | Auxientius | Auxilius | Avitus | Balbillus |
| Balbus | Balduinus | Bambalio | Bamballio | Banquerius | Barbatus |
| Baro | Bartolomaeus | Bassus | Bato | Belenus | Belisarius |
| Bellator | Belletor | Bellicus | Bellus | Benigius | Bestia |
| Betto | Bibaculus | Bibulus | Bitucus | Blaesus | Blandus |
| Blassianus | Bodenius | Bolanus | Bonosus | Bonus | Bradua |
| Bromidus | Bruccius | Brucetus | Bruscius | Brutus | Bubo |
| Bulla | Burcanius | Burrus | Buteo | Caecilianus | Caecina |
| Caecus | Caelestis | Caelestius | Caelianus | Caelinus | Caepio |
| Caerellius | Caesar | Caesoninus | Calacicus | Calatinus | Caldus |
| Calenus | Calerus | Caletus | Caligula | Callisunus | Calogerus |
| Calpornius | Calpurnianus | Calpurnis | Calvinus | Calvus | Camerius |
| Camillus | Campanus | Candidus | Canidius | Canio | Canisius |
| Cantaber | Capito | Capiton | Caprarius | Caracturus | Carantus |
| Carausius | Carbo | Carisius | Carius | Carnifex | Casca |
| Cassianus | Castorius | Castus | Catianus | Catilina | Cato |
| Catonius | Catsuminianus | Catullus | Catulus | Catus | Cecilianus |
| Celer | Celsus | Cenaeus | Cencius | Censorinus | Censorius |
| Centumalus | Cerialis | Cervianus | Cervidus | Cethegus | Chilo |
| Christianus | Cicero | Cico | Cimber | Cinna | Cinnianus |
| Cita | Cittinus | Civilis | Clarus | Classicianus | Classicus |
| Claudianus | Clemens | Clement | Clodian | Clodianus | Cocceianus |
| Cogitatus | Colias | Collatinus | Columbanus | Columella | Comes |
| Comitianus | Comitinus | Commidius | Commidus | Commius | Compitalicius |
| Concessus | Condrausisius | Congrio | Consrotius | Constans | Constantius |
| Contumeliorus | Corbulo | Cordus | Cornix | Cornutus | Corvinus |
| Cotentinus | Cotta | Crassus | Cremutius | Crescentius | Cresces |
| Crispian | Crispin | Crispus | Crito | Crotilo | Cucuphas |
| Culleolus | Cumanus | Cunctator delayer | Cunobarrus | Cupitus | Curio |
| Cyprianus | Cyprias | Dacian | Dagwalus | Dama | Damasippus |
| Dannicus | Dardanius | Dardanus | Decianus | Decmitius | Decmus |
| Decuminus | Delicius | Desideratus | Dexion | Dexippus | Didacus |
| Dignus | Dio | Diocletianus | Dioscourides | Disertus | Docilinus |
| Docilis | Dolabella | Dominicus | Domitianus | Donatianus | Donatus |
| Donicus | Drusillus | Drusus | Dubitatus | Durio | Durus |
| Duvianus | Eborius | Eburnus | Ecdicius | Eclectus | Egbutius |
| Egnatius | Elerius | Eleutherius | Eliphias | Elvorix | Emeritus |
| Encratis | Ennecus | Ennius | Eonus | Epidianus | Epimachus |
| Epitynchianus | Epolonius | Erasinus | Esdras | Eudomius | Eugenius |
| Eugenus | Eumenius | Eunapius | Eustacius | Eutherius | Evodius |
| Excingus | Exsupereus | Exuperantius | Exupertus | Fabianus | Fabillus |
| Facilis | Fadus | Fagus | Falco | Falconius | Falx |
| Famia | Familiaris | Fastidius | Faustillus | Faustinianus | Faustinius |
| Faustus | Felicissimus | Felissimus | Felix | Ferentinus | Ferreolius |
| Festus | Fidelis | Figulus | Fimbria | Fimus | Firminus |
| Firmus | Flaccus | Flavian | Flavianus | Flavillus | Flavinus |
| Florens | Florianus | Forianus | Fortunatus | Fraucus | Fredisius |
| Frigidian | Frontalis | Frontinus | Fronto | Fructosis | Frugi |
| Frugius | Frumentius | Fullofaudes | Fulvianus | Funisulanus | Furius |
| Fuscinus | Fuscus | Gaianus | Gaius | Gala | Galarius |
| Galerus | Gallus | Galvisius | Garilianus | Gaurus | Gavros |
| Gavrus | Gelasius | Gellius | Gemellus | Geminianus | Generidus |
| Genesius | Genialis | Gerardus | Gessius | Geta | Getha |
| Glabrio | Glaucia | Globulus | Gluvias | Glycia | Gordianus |
| Gordio | Gorgonius | Gracchus | Gracilis | Gratidianus | Grumio |
| Gualtierus | Habitus | Hadrianus | Hardalio | Haterius | Helvius |
| Herculius | Herenus | Herma | Hermina | Hesychius | Hiberus |
| Hieronimianus | Hilario | Hilaris | Hilarius | Hirpinius | Hirrus |
| Homullus | Horatius | Hortensius | Hosidius | Humilis | Hyacinthus |
| Hybrida | Iacomus | Igennus | Indaletius | Indus | Ingenuus |
| Ingenvinus | Iocundus | Isatis | Italicus | Ivimarus | Januarius |
| Javolenus | Jovinianus | Jovinus | Jovius | Juba | Julian |
| Julianus | Juncinus | Juncus | Junianus | Justianus | Justin |
| Justinianus | Justinus | Justus | Juvenalis | Kaeso | Lactantius |
| Laeca | Laenas | Laetinianus | Laevinus | Larcius | Lartius |
| Lateranus | Latinus | Laurentius | Leddicus | Lentullus | Lentulus |
| Leon | Lepidus | Lepontus | Leptis | Libanius | Liberalis |
| Libo | Licinianus | Licinius | Ligur | Ligustinus | Limetanus |
| Linus | Litorius | Littera | Litumarus | Livianus | Livigenus |
| Lovernianus | Lovernius | Lucan | Lucanus | Lucianus | Lucilianus |
| Lucretinaus | Lucretius | Luctacus | Lucullus | Lunaris | Luonercus |
| Lupercus | Lupicinus | Lupinus | Lupus | Lurco | Lurio |
| Lutherius | Lutorius | Maccalus | Macrinus | Macro | Macrobius |
| Mactator | Maecenas | Maecius | Magnus | Magunnus | Maius |
| Major | Malchus | Mallus | Maltinus | Maminianus | Mancinus |
| Manlius | Mansuetus | Marcellinus | Marcellus | Marcialis | Marcipor |
| Margarita | Marinianus | Marinus | Maritimus | Marius | Maro |
| Marsicus | Marsus | Marsyas | Martial | Martialis | Martianus |
| Martinus | Martius | Marullinus | Marullus | Maternus | Matho |
| Maursus | Maximian | Maximinius | Maximus | Medullinus | Megellus |
| Melissus | Melitus | Mellitus | Melus | Meminius | Memmius |
| Memor | Mercator | Mercurialis | Mercurinus | Merula | Messala |
| Messor | Metellus | Metilius | Metunus | Micianus | Mico |
| Milonius | Minervalis | Minianus | Minicianus | Moderatus | Molacus |
| Momus | Montanus | Montaus | Mordanticus | Mucianus | Muco |
| Muncius | Murena | Mus | Musa | Musicus | Mutilus |
| Mutius | Nabor | Naevius | Namatianus | Narcissus | Nasica |
| Naso | Natalinus | Natalis | Naucratius | Nazarius | Nectaridus |
| Nelius | Nemesianus | Nemnogenus | Neneus | Nennius | Nepos |
| Nero | Nertomarus | Nerva | Nicasius | Nigellus | Niger |
| Nigidius | Nigrinus | Niraemius | Nolus | Nonius | Noster |
| Novatian | Novellius | Numerianus | Numonis | Oceanus | Octavian |
| Octavianus | Octobrianus | Olennius | Olympicus | Opimius | Opis |
| Optatus | Orientalis | Orientius | Orissus | Orosius | Ostorianus |
| Pacatianus | Pachomius | Pacuvianus | Paenula | Paetinus | Paetus |
| Palicamus | Pamphilius | Panaetius | Pansa | Pantenus | Pantera |
| Panthera | Papinian | Papus | Paratus | Parnesius | Pascentius |
| Paterculus | Patiens | Paulinus | Paullus | Pavo | Pennus |
| Peregrinus | Perennis | Perpenna | Perperna | Pertacus | Pertinax |
| Petasius | Petreius | Petronax | Petrus | Philippus | Pictor |
| Pilatus | Pilus | Pinarius | Piso | Pius | Placidus |
| Planta | Plautis | Plautius | Plautus | Pleminius | Pollienus |
| Pollio | Polus | Polybius | Pompolussa | Pomponius | Poplicola |
| Porcus | Porphyrius | Postumianus | Postumus | Potitus | Praetextus |
| Prilidianus | Primanus | Primulus | Primus | Prisca | Priscillian |
| Priscillianus | Priscus | Processus | Proceus | Proculus | Procyon |
| Profuterius | Propertius | Propinquus | Protacius | Protus | Proxsimus |
| Publianus | Publicola | Pudens | Pudentius | Pulcher | Pulcherius |
| Pullus | Pusinnus | Pustula | Quartinus | Quarto | Quatruus |
| Quentin | Quietus | Quintilianus | Quintilius | Quintillius | Quintillus |
| Quiriac | Quiricus | Quirinalis | Ramio | Ramirus | Ravilla |
| Reburrus | Receptus | Rectus | Regillus | Reginus | Regulus |
| Remigius | Remus | Renatus | Respectus | Restitutus | Rex |
| Ripanus | Rogelius | Romanus | Romulianus | Romulus | Roscius |
| Rufinianus | Rufinus | Rufrius | Rufus | Rullus | Ruricius |
| Ruso | Rusticus | Rutilianus | Sabellius | Sabinianus | Sabinus |
| Saenus | Salinator | Salonianus | Saloninus | Salonius | Salvianus |
| Salvius | Sanctus | Sandilianus | Sanga | Sarimarcus | Sarrius |
| Saturninus | Saunio | Scaevola | Scapula | Scaro | Scato |
| Scaurus | Schlerus | Scipio | Scribonianus | Scrofa | Secundus |
| Segestes | Sejanus | Sellic | Seneca | Senecianus | Senecio |
| Senilis | Senna | Senopianus | Sentius | Septimianus | Sergius |
| Seronatus | Serranus | Sertorius | Servanus | Servatius | Servilius |
| Seuso | Severinus | Sevso | Siculus | Sidonius | Sigilis |
| Silanus | Silius | Silo | Silus | Silvanus | Similis |
| Simo | Simplex | Simplicianus | Siricus | Sisenna | Sisinnius |
| Sita | Sollemnis | Sorex | Sorio | Sosius | Soterichus |
| Sotericus | Soulinus | Spartacus | Spendius | Speratus | Statius |
| Stichus | Strabo | Sudrenus | Suilius | Sulinus | Sulla |
| Sulpicius | Super | Superbus | Superstes | Sura | Surinus |
| Surius | Surus | Sylla | Sylvian | Sylvius | Symmachus |
| Symphorian | Sympronian | Synistor | Synnodus | Tacitus | Taenarus |
| Tancinus | Tanicus | Tarquinius | Tarsicius | Tasius | Tatian |
| Tatianus | Taurinus | Taurus | Telesinus | Terenteianus | Tertius |
| Tertullian | Tertullianus | Tertulus | Tetricus | Tetullianus | Thrasea |
| Tiberillus | Tiberinus | Tibullus | Tiburs | Tiburtius | Ticinus |
| Titianus | Titillus | Torquatus | Toutius | Traianus | Traillus |
| Tranio | Tranquillus | Trebellius | Trebius | Trebonianus | Trebonius |
| Tremerus | Tremorinus | Trenico | Trenus | Triarius | Trifer |
| Triferus | Trimalchio | Trogus | Trupo | Tuccianus | Tuditanus |
| Tullius | Tullus | Turibius | Turpilianus | Turpilinus | Turpilius |
| Tuticanus | Tutor | Typhoeus | Tyranus | Ulfila | Ulixes |
| Ulpian | Umbonius | Ursacius | Ursinus | Ursus | Uticensis |
| Vala | Valens | Valentinian | Valentinus | Valerianus | Valgus |
| Varialus | Varro | Varus | Vatia | Vedrix | Vegetius |
| Velus | Venator | Ventor | Venustinius | Vepgenus | Veranius |
| Verecundus | Vergilius | Verinus | Verres | Verrucosis | Verullus |
| Verulus | Verus | Vespasianus | Vestinus | Vestorius | Vetranio |
| Vettonianus | Veturius | Vibennis | Vibius | Vibullius | Victor |
| Victricius | Vincentius | Vindex | Vinicianus | Vipsanius | Virginius |
| Viridio | Virilis | Virnius | Vitalinus | Vitalion | Vitalis |
| Vitoricus | Vitulus | Vitus | Vocula | Volturcius | Volusenus |
| Volusianus | Vonones | Vopiscus | Voteporix | Vulso | Zosimus |
Some cognomina commemorated a successful military campaign against a particular country or area. They were usually taken by the commanding officer. They could also signify fondness for or connections with a particular area. Male
| Africanus | Allobrogicus | Asiaticus | Atticus | Balearicus | Briganticus |
| Britannicus | Creticu | Cyriacus? | Dalmaticus | Gaetulicus? | Gallicus |
| Germanicus | Glycoricus? | Helveticus | Isauricus | Macedonicus | Numidicus |
| Spartacus |
Female
| Balearica | Cretica | Dalmatica |
This was often a feminine form of the father's but by the C1st BC, many women had their own cognomen (such as 'Pulchra', beautiful or 'Parva', small) or one describing their position in the family: 'Major', the Elder or 'Minor', the Younger. On marriage, they took the genitive form of their husband's name e.g. 'Antonia Pompeii' - Antonia, wife of Pompeius.
| Aeliana | Aeterna | Afrania | Afrodisia | Agneta | Agrippina |
| Aia | Amabilis | Amalthea | Amanda | Apicata | Apphia |
| Apronia | Apulia | Arruntia | Astia | Atia | Augusta |
| Aventina | Avita | Blatta | Byrria | Caepionis | Caesonia |
| Calva | Camilla | Capitolina | Carina | Casta | Cata |
| Catia | Caula | Censorina | Cherusca | Christiana | Cinna |
| Clara | Cloelia | Columella | Concessa | Cordelia | Cosconia |
| Cotta | Coventina | Crescentia | Crispina | Cristina | Cypria |
| Decima | Desiderata | Dinysia | Dolichena | Domna | Dulcilla |
| Emelia | Emerentiana | Encratia | Ennia | Erigena | Estella |
| Eubala | Eubia | Eutropia | Fausta | Faustina | Faustinia |
| Fecenia | Felicia | Felicula | Fesonia | Flora | Fontia |
| Fortunata | Gaea | Gaetulica | Galla | Geneura | Gloria |
| Gnaea | Graecina | Grata | Hilara | Hilaria | Honora |
| Hypatia | Iana | Idonea | Indara | Ingenua | Innocentia |
| Januaria | Jovina | Juliana | Julilla | Julitta | Juncina |
| Justa | Justina | Lanilla | Larina | Laureola | Laurina |
| Lavinia | Lepida | Lesbia | Licinian | Livigena | Longina |
| Luciana | Lucilla | Lucina | Lupula | Lutatia | Macrina |
| Maesa | Maia | Mallea | Mamaea | Mamma | Mammiola |
| Mansueta | Mariana | Marina | Martia | Martina | Martiola |
| Matrona | Maxilla | Maxima | Maximilla | Messalina | Messina |
| Metella | Metiliana | Milvia | Myrtilla | Naissa | Narcissa |
| Natalia | Nobilioris | Numantina | Occia | Ocresia | Olivia |
| Oriuna | Pacata | Palla | Panthea | Pantheria | Pascentia |
| Paulla | Peregrina | Petraea | Phrygia | Pinta | Placida |
| Planasia | Plancina | Plautia | Plotina | Pluma | Pompeia |
| Poppaea | Porcella | Postimia | Potamiaena | Praxedes | Prenestina |
| Priscilla | Procilla | Procula | Pulchra | Pussitta | Regina |
| Restita | Rhea | Ria | Romana | Sabina | Sabrina |
| Sacrata | Salonia | Salviena | Sapientia | Saturnia | Saturnina |
| Scaura | Scipionis | Secunda | Selene | Selina | Serena |
| Severa | Severiana | Silana | Silicia | Silvia | Simplicia |
| Sophrona | Sosia | Sulpicia | Tacita | Tarpeia | Tebetta |
| Teracina | Tertia | Tertulla | Thena | Tiberia | Titullinia |
| Trifosa | Tristonia | Tuomina | Ulidia | Una | Ursula |
| Utica | Vacia | Vecchia | Velva | Velvinna | Vernico |
| Veronica | Viatrix | Vibidia | Victoria | Victorina | Vilbia |
| Vinicia | Virgilia | Virginia | Viventia | Volumnia | Xiphilina |
| Zonara |
This collection of names compiled by Kate Monk. Copyright January 1997, Kate Monk. Last updated May, 99. Copies may be made for personal use only.