weir: [OE] A weir is etymologically a structure for ‘hindering’ the flow of water. The word’s Old English ancestor was derived from the verb werīan ‘defend, protect’, also ‘hinder’, and hence by extension ‘dam up’, which was distantly related to Sanskrit vr ‘cover’ and vāraya ‘stop, hinder’, and came ultimately from the Indo-European base *wer- ‘cover, shut’. [weir etymology, weir origin, 英语词源]