Go to Dictionary.Reference.com and type “retweet” and this is what you will get
verb (used with object)1.to share or forward (someone else’s message) on the Twitter Web site.
2.a message that has been shared or forwarded on Twitter: the most popular retweets.
There are 400 new worlds and phrases in the 12th edition of Concise Oxford English Dictionary, the abridged version of the Oxford English Dictionary.
Some of the new words, courtesy of CNN blog:
– cyberbullying: n. the use of electronic communication to bully a person, typically by sending messages of an intimidating or threatening nature.
– jeggings: pl. n. tight-fitting stretch trousers for women, styled to resemble a pair of denim jeans.
– mankini: n. (pl. mankinis) a brief one-piece bathing garment for men, with a T-back.
– retweet: v. (on the social networking service Twitter) repost or forward (a message posted by another user). n. a reposted or forwarded message on Twitter.
– sexting: n. informal the sending of sexually explicit photographs or messages via mobile phone.
– woot: exclam. informal (especially in electronic communication) used to express elation, enthusiasm, or triumph.