tweet

A  tweet  is a note (or reply) posted on Twitter.

2006
2006-11-14 Before "tweet" meant a post on Twitter. The Twitter blog post Six More Twitter Updates! refers to Twitter posts by other terms ( emphasis added )
 * singular "Twitter update" as in "When you come across a Twitter update that you really like you can save it by clicking the little star."
 * plural "Twitters" as in "[…] pick favorites we can put together fun pages like the Top 10 Favorite Twitters .(Note: The Top 10 […]"

2007
2007: The term "tweet" to refer to Twitter posts was introduced in the Twitterific app