a fictitious name used by an author to conceal his or her identity; pen name.
Compare allonym (def. 1).
Origin of pseudonym
First recorded in 1840–50; from Greek pseudṓnymon “false name”; see pseud-, -onym
SYNONYMS FOR pseudonym
alias, nom de plume.
SEE SYNONYMS FOR pseudonym ON THESAURUS.COM
historical usage of pseudonym
The English noun pseudonym comes via the French adjective and noun pseudonym, in French originally meaning “(pertaining to) one who writes or publishes under an alias,” and then “(pertaining to) a name chosen by someone to conceal his or her identity.” The Greek origin of pseudonym (and even of its parts) is pretty obvious: Greek pseudṓnymos “under a false name, falsely called” is a compound whose first element pseudo- “false, lying” is a combining form of pseûdos “a lie.” The second element -ṓnymos is a combining form deriving from the noun ónoma (Doric and Aeolic ónyma ) “name.” The English noun appeared in the early 1800s, but the adjective pseudonymous was recorded more than a century earlier, in Edward Phillips’s 1706 dictionary New World of Words.