Zoology= "pinnule".
Early 18th century (in an earlier sense). From classical Latin pinnula little feather, little wing, little fin from pinna feather, wing, fin + -ula.
英汉双解词典包含464360条英汉词条，基本涵盖了全部常用单词的翻译及用法，是英语学习的有利工具。