wag

American Heritage® Dictionary of the English Language, Fourth Edition

1. v. To move briskly and repeatedly from side to side, to and fro, or up and down.
2. v. To move rapidly in talking. Used of the tongue.
3. v. To walk with a clumsy sway; waddle.
4. v. Archaic To be on one's way; depart.
5. v. To move (a body part) rapidly from side to side or up and down, as in playfulness, agreement, admonition, or chatter.
6. n. The act or motion of wagging: a farewell wag of the hand.
7. n. A humorous or droll person; a wit.

Century Dictionary and Cyclopedia

1. To cause to move up and down, backward and forward, or from side to side, alternately, as a small body jointed or attached to, or connected with, a larger one; cause to move one way or another, as on a pivot or joint, or on or from something by which the body moved is supported; cause to shake, oscillate, or vibrate slightly. From the quick, jerky, or abrupt motion indicated by the word, an idea of playful, sportive, mocking, scornful, or derisive motion is associated with it in certain phrases: as, to wag the head or the finger.
2. To nudge.
3. To move backward and forward, up and down, or from side to side, alternately, as if connected with a larger body by a joint. pivot, or any flexible or loose attachment; oscillate; sway or swing; vibrate: an arrow is said to wag when it vibrates in the air.
4. To be in motion or action; make progress; continue a course or career; stir.
5. To move on or away; be off; depart; pack off; be gone.
6. n. The act of wagging; a shake; an oscillation.
7. n. One who is given to joking or jesting; a witty or humorous person; one full of sport and humor; a droll fellow. The word seems formerly to have been applied to a person who indulged in coarse, low, or broad humor, or buffoonery, as a practical joker.
8. n. A fellow: used with a shade of meaning sometimes slurring, sometimes affectionate, but without any attribution of humor or pleasantry.

Wiktionary

1. v. To swing from side to side, especially of an animal's tail
2. v. To not go to school, either for a class or classes or the entire school day;1 play the wag; hop the wag; wag it.2
3. n. An oscillating movement.
4. n. A witty person.

GNU Webster's 1913

1. v. 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.
2. v. To move one way and the other; to be shaken to and fro; to vibrate.
3. v. To be in action or motion; to move; to get along; to progress; to stir.
4. v. To go; to depart; to pack oft.
5. n. The act of wagging; a shake.
6. n. A man full of sport and humor; a ludicrous fellow; a humorist; a wit; a joker.

WordNet 3.0

1. n. causing to move repeatedly from side to side
2. v. move from side to side
3. n. a witty amusing person who makes jokes