%sheet anchor%

[ OE. scheten to shoot, AS. sceótan; cf. OE. shoot anchor. See Shoot, v. t. ] 1. (Naut.) A large anchor stowed on shores outside the waist of a vessel; -- called also waist anchor. See the Note under Anchor. [ 1913 Webster ]

2. Anything regarded as a sure support or dependence in danger; the best hope or refuge. [ 1913 Webster ]