pseu ‧ do ‧ nym /ˈsjuːd ə nɪm $ ˈsuː-/ BrE AmE noun [countable]
[ Date: 1800-1900 ; Language: French ; Origin: pseudonyme , from Greek pseudonymos 'having a false name' ]
an invented name that a writer, artist etc uses instead of their real name SYN nom de plume
under a pseudonym
He wrote under the pseudonym ‘Silchester’.
—pseudonymous /sjuːˈdɒnəməs, sjuːˈdɒnɪməs $ suːˈdɑː-/ adjective :
He was the pseudonymous author.
—pseudonymously adverb