Scrag (skrăg), n. [Cf. dial. Sw. skraka a great dry tree, a long, lean man, Gael. sgreagach dry, shriveled, rocky. See Shrink, and cf. Scrog, Shrag, n.] 1. Something thin, lean, or rough; a bony piece; especially, a bony neckpiece of meat; hence, humorously or in contempt, the neck.
Lady MacScrew, who... serves up a scrag of mutton on silver. Thackeray.
2. A rawboned person. Halliwell.
3. A ragged, stunted tree or branch.
Scrag whale(Zoöl.), a North Atlantic whalebone whale (Agaphelus gibbosus). By some it is considered the young of the right whale.