late 13c., penne, "writing implement made from the hard, hollow stem at the base of a feather," from Old French pene "quill pen; feather" (12c.) and directly from Latin penna "a feather, plume," in plural "a wing," in Late Latin, "a pen for writing," from Old Latin petna, pesna, from PIE *pet-na-, suffixed form of root *pet- "to rush; to fly."
In later French, this word means only "long feather of a bird," while the equivalent of English plume is used for "writing implement;" the senses of the two words in French thus are reversed from the situation in English.
In Middle English also "a feather," especially a large one from the wing or tail. The sense was extended to any instrument of similar form used for writing by means of fluid ink. Pen-and-ink (adj.) "made or done with a pen and ink" is attested from 1670s. Pen name "fictitious name assumed by an author" is recorded from mid-19c. (French nom de plume was used in English from 1823). Southey uses pen-gossip (v.) "to gossip by correspondence" (1818).