1. To pinch, pluck, or twist sharply: "Her son is very annoyed when his aunt has to tweak his cheek."
2. To adjust; to fine-tune: "The company may have to tweak the software program once more."

To utter a weak chirping sound: "Rescue efforts of the man and woman were hampered by the flocks of birds that continued to tweet as they circled the couple's heads."

A post or status update on Twitter, a microblogging service: "Because Twitter only allows messages of 140 characters or less, tweet is as much a play on the size of the message as it is on the audible similarity to Twitter."

A small loudspeaker designed to reproduce high-pitched sounds in a high-fidelity audio system: "We had to adjust the tweeter on our speaker."

A meeting or other gathering organized by means of posts on the social networking service Twitter (from tweet + up, based on the word meetup): "Her sister had quite a party after tweeting a tweetup to the twits that she knows."

To taunt, to ridicule, or to tease; especially, for an embarrassing mistake or fault: "He continued to twit his mother long after it stopped being humorous."

A foolish person: "He is a twit who always wants to tweet on Twitter."

To make fast and usually high sounds: "I could hear the bird twitter in the tree outside my bedroom window."

1. The short, high sounds that birds can make: "The twitter of songbirds filled the air."
2. In a twitter refers to being very nervous or excited about something: "She was all in a twitter about the birthday party."
3. A mini-blogging social-network service that lets a person update friends on what is going on at any particular moment: "Twitter allows blog posts of only 140 characters, which is just large enough for a sentence, or two, if they are very short."
4. A social networking and micro-blogging service that allows its users to send and to read other users' updates (known as tweets): "In March, 2009, Garry Trudeau's Doonesbury strip started to satirize Twitter, with the strip characters ironically highlighting the triviality of tweets and Roland, a character in the strip, defending the need to keep up with the constant-update trend or lose relevance in today's society."