"many-stemmed woody plant," Old English bysc, from West Germanic *busk "bush, thicket" (cf. Old Saxon and Old High German busc, Dutch bosch, bos, German Busch). Influenced by or combined with cognate words from Scandinavian (cf. Old Norse buskr, Danish busk, but this might be from West Germanic) and Old French (busche "firewood," apparently of Frankish origin), and also perhaps Anglo-Latin bosca "firewood," from Medieval Latin busca (whence Italian bosco, Spanish bosque, French bois), which apparently also was borrowed from West Germanic; cf. Boise.
In British American colonies, applied from 1650s to the uncleared districts, hence "country," as opposed to town (1780); probably originally from Dutch bosch in the same sense, because it seems to appear first in English in former Dutch colonies. Meaning "pubic hair" (especially of a woman) is from 1745. To beat the bushes (mid-15c.) is a way to rouse birds so that they fly into the net which others are holding, which originally was the same thing as beating around the bush (see beat (v.)).