From Old English 'behindan' (by + from behind), from Proto-Germanic *hinda — related to 'hinder' and 'hindsight.'
At or to the back or far side of something.
From Old English 'behindan' (at the back of, after), composed of 'be-' (by, near, at) + 'hindan' (from behind, at the rear), from Proto-Germanic *hinda- (behind, back), possibly from PIE *ḱem- (with, along, beside) via a suffixed form, though the connection is uncertain. The element 'hind-' is the core spatial term, also appearing in 'hinder' (to obstruct — literally 'to keep at the back'), 'hindrance,' and 'hind' (the rear, as in 'hind legs'). The Proto-Germanic *hinda- has cognates in Gothic 'hindana' (behind, beyond), Old High
The 'hind' in 'behind' is the same element in 'hinder' (to hold back), 'hindrance,' 'hindsight' (seeing what is behind you in time), and 'hind legs' (the back legs of an animal). A 'hind' (a female deer) is a different word entirely, from Old English 'hind' via Proto-Germanic '*hindō.' The casual noun 'behind' meaning 'buttocks' dates to the 18th century — a polite euphemism that locates the body part by its position rather than naming