Webster’s Revised Unabridged Dictionary · 1913
Pecopteris
Pe·cop′te·ris (pē·kŏp′tē·rĭs), n. [NL., fr. Gr. πέκειν to comb + πτερίς a kind of fern.] (Paleon.) An extensive genus of fossil ferns; — so named from the regular comblike arrangement of the leaflets.