Pennaceous

Part of speech: adjective

Definitions

1. Having characteristics or qualities similar to those of a feather
2. Describing something that is featherlike in form or texture
3. Pertaining to or resembling the structure or appearance of feathers

Etymology: "Pennaceous" is a technical term from botany and zoology, used of things that are feather-like in form, such as the vane structure of a feather or the way certain hairs or bristles are shaped. Its history is plain: it combines the Latin "penna," meaning "feather," with the suffix "-aceous," which turns a noun into an adjective meaning "of the nature of" or "resembling" the noun. English formed the adjective by attaching that suffix to the Latin stem. The suffix "-aceous" itself came into English from Latin "-aceus," which was used to describe something made of, or resembling, a material or substance. Many scientific adjectives built this way describe a resemblance rather than an identity, so "pennaceous" means something like "feather-ish" rather than "made of feather."