Modern usages of the words tweet, fascinator, pay day loan and flash mob are all among a host of new additions to the Oxford English Dictionary.

The centuries-old publication even said it had to break a rule to force through a word which has seen a dramatic spike in usage since 2006.

OED chief editor John Simpson wrote - perhaps appropriately - a blog to explain:

The noun and verb tweet (in the social-networking sense) has just been added to the OED. This breaks at least one OED rule, namely that a new word needs to be current for ten years before consideration for inclusion. But it seems to be catching on.

Among the 1200 new words were also:

  • tweet, v. To post (a message, item of information, etc.) on Twitter. Also: to post a message to (a particular person, organization, etc.).

  • tweet, n. A posting made on the social networking service Twitter.

  • tweet, n. A posting made on the social networking service Twitter.

  • follower, n. A person who follows a particular person, group, etc., on a social media website or application.

  • geekery, n. subject or pursuit, esp. one regarded as unfashionable or highly technical. Also: the state of being a geek; geekiness.

  • pay day loan, n. chiefly U.S. a type of small, short-term loan at a high rate of interest, typically used by borrowers to cover expenses while awaiting their next wages.

  • mouseover, n. The action of moving the pointer on to an element of a graphical user interface or web page; an event (esp. a visual change) triggered by this.

  • crowdsourcing, n. The practice of obtaining information or services by soliciting input from a large number of people, typically via the Internet and often without offering compensation.

  • fiscal cliff, n. A situation in which a particular set of financial factors causes or threatens sudden and severe economic decline.

  • flash mob, n. A large group of people organized by means of the Internet, or mobile phones or other wireless devices, who assemble in public to perform a prearranged action together and then quickly disperse.

  • fascinator, n. Originally: a woman’s hat incorporating a piece of netting that veils or partially veils the face. Now usually: a woman's light, decorative headpiece, typically comprising a comb, hair clip, or headband decorated with feathers, flowers, netting, etc.

  • dad dancing, n. colloq. (orig. and chiefly Brit.) an awkward, unfashionable, or unrestrained style of dancing to pop music, as characteristically performed by middle-aged or older men.

See the OED's full new word list June 2013 here.