Wag \Wag\, v. i.

1. To move one way and the other; to be shaken to and fro; to vibrate.

The resty sieve wagged ne'er the more. --Dryden.

2. To be in action or motion; to move; to get along; to progress; to stir. [Colloq.]

``Thus we may see,'' quoth he, ``how the world wags.'' --Shak.

3. To go; to depart; to pack oft. [R.]

I will provoke him to 't, or let him wag. --Shak.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Wag \Wag\, n. [From Wag, v.]

1. The act of wagging; a shake; as, a wag of the head. [Colloq.]

2. [Perhaps shortened from wag-halter a rogue.]

A man full of sport and humor; a ludicrous fellow; a humorist; a wit; a joker.

We wink at wags when they offend. --Dryden.

A counselor never pleaded without a piece of pack thread in his hand, which he used to twist about a finger all the while he was speaking; the wags used to call it the thread of his discourse. --Addison.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Wag \Wag\, v. t. [imp. & p. p. Wagged; p. pr. & vb. n. Wagging.]

[OE. waggen; probably of Scand. origin; cf. Sw. vagga to rock a cradle, vagga cradle, Icel. vagga, Dan. vugge; akin to AS. wagian to move, wag, wegan to bear, carry, G. & D. bewegen to move, and E. weigh. [root]136. See Weigh.]

To move one way and the other with quick turns; to shake to and fro; to move vibratingly; to cause to vibrate, as a part of the body; as, to wag the head.

No discerner durst wag his tongue in censure. --Shak.

Every one that passeth thereby shall be astonished, and wag his head. --Jer. xviii. 16.

Note: Wag expresses specifically the motion of the head and body used in buffoonery, mirth, derision, sport, and mockery.

Source: Webster's Revised Unabridged Dictionary (1913)