Is it ensure, insure, or assure?
1540s, "lean person or animal, a raw-bones;" perhaps from a Scandinavian source (cf. Norwegian skragg "a lean person;" dialectal Swedish skraka "a great, dry tree; a long, lean man," skragge "old and torn thing," Danish skrog "hull of a ship, carcass," Icelandic skröggr, a nickname of the fox); perhaps from root of shrink.
An unattractive woman; dog
[1940s+ Students; probably fr hag reinforced by the name of the ugly Scraggs family in the comic strip ''Li'l Abner'' and possibly by earlier slang, ''a raw-bones; a skinny person,'' found by 1542]