Partly a back-formation of wreathen (past participle of writhe), and partly from wreath.
wreathe (third-person singular simple present wreathes, present participle wreathing, simple past and past participle wreathed)
- (transitive) To twist, curl or entwine something into a shape similar to a wreath
- (transitive) To form a wreathlike shape around something
- (intransitive) To curl, writhe or spiral in the form of a wreath
- (obsolete) To turn violently aside or around; to wrench.
- 1590, Edmund Spenser, The Faerie Queene, II.i:
- from so heauie sight his head did wreath, / Accusing fortune, and too cruell fate [...].
twist into a shape similar to a wreath