n. pl. cog·no·mens or cog·nom·i·na (-nŏmə-nə)
a. A family name; a surname.
b. The third and usually last name of a citizen of ancient Rome, as Caesar in Gaius Julius Caesar.
2. A name, especially a descriptive nickname or epithet acquired through usage over a period of time.
[Latin cognōmen : co-, con-, co- (influenced by cognōscere, to know) + nōmen, name; see n-men- in the Appendix of Indo-European roots.]
cog·nomi·nal (-nŏmə-nəl) adj.
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