wag¹ / wag/ • v. (wagged, wag·ging) (with reference to an animal's tail) move or cause to move rapidly to and fro: [intr.] his tail began to wag | [tr.] the dog went out, wagging its tail. ∎  [tr.] move (an upward-pointing finger) from side to side to signify a warning or reprimand: she wagged a finger at Elinor. ∎  [intr.] (used of a tongue, jaw, or chin, as representing a person) talk, esp. in order to gossip or spread rumors: this is a small island, and tongues are beginning to wag.• n. a single rapid movement from side to side: a chirpy wag of the head.PHRASES: how the world wags dated how affairs are going or being conducted.the tail wags the dogsee tail¹ .wag² • n. dated a person who makes facetious jokes.

wag1 tr. †stir, move XIII; sway from side to side XIV; intr. †brandish, wave XIII; move to and fro XIV. ME. waggen, iterative formation on OE. wagian totter, sway), ME. waʒe, waw(e) = MLG., MDu. wagen, OHG. wagōn, ON. vaga.
So waggle XV; see -LE3 and cf. (M)LG., Du. waggelen stagger, totter, which may be the immed. source.

wag2 mischievous boy, youth, chap; habitual joker. XVI. prob. shortening of †waghalter (vars. †wagstring, †wagwith) one who is likely to swing in the hangman's noose, gallows-bird XVI; see prec., HALTER.
Hence waggery, waggish XVI.

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