From Longman Dictionary of Contemporary Englishpen nameˈpen name noun [countable] ALNAME OF A PERSONa name used by a writer instead of their real name SYN pseudonym, nom de plume
Examples from the Corpus
pen name• Under yet another pen name, Leo starts writing scathing reviews of her own books for a newspaper literary supplement.• Cassandra, appropriately, considering his pen name, was not believed.• It was signed in Charlotte's male pen name. 