nudge

from The American Heritage® Dictionary of the English Language, 5th Edition.

• transitive verb To push against gently, especially in order to gain attention or give a signal.
• transitive verb To come close to; near.
• noun A gentle push.

from The Century Dictionary.

• noun A slight push, as with the elbow; a covert jog intended to call attention, give warning, or the like.
• To touch gently, as with the elbow; give a hint or signal to by a covert touch with the hand, elbow, or foot.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb To touch gently, as with the elbow, in order to call attention or convey intimation.
• noun A gentle push, or jog, as with the elbow.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A gentle push.
• noun Internet A feature of instant messaging software used to get the attention of another user, as by shaking the conversation window or playing a sound.
• noun The rotation by one step of a reel of the player's choice.
• verb transitive To push against gently, especially in order to gain attention or give a signal
• verb transitive To near or come close to something

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• verb push into action by pestering or annoying gently
• verb to push against gently
• noun a slight push or shake