You can use the word bird as a verb meaning "to observe birds as a hobby," and in some places, particularly Britain, it's also a noun meaning "young woman." Bird is an Old English word, an unusual form of bridd, "young bird or fledgling," from an unknown origin.

Is Birded a word?

Objectionable or worthless. [Middle English, from Old English brid, young bird.] bird′ing n.

Is birds an adverb or adjective?

bird (noun) bird's–eye (adjective)