VERB:
Chiefly New England, Midland U.S., & Southern U.S.
Variant of get.
http://education.yahoo.com/reference/dictionary/entry/git
British informal
an unpleasant or contemptible person
http://www.oxforddictionaries.com/definition/git?view=uk
http://www.macmillandictionary.com/dictionary/american/git
Usage notes
'Git' is usually used as an insult, more severe than twit but less severe than a true profanity like wanker or ********, and may often be used affectionately between friends. 'Get' can also be used, with a subtle change of meaning. 'You cheeky get!' is slightly less harsh than 'You cheeky git!'.
'Git' is frequently used in conjunction with another word to achieve a more specific meaning. For instance a "smarmy git" refers to a person of a slimy, ingratiating disposition; a "jammy git" would be a person with undeserved luck. The phrase "grumpy old git", denoting a cantankerous old man, is used with particular frequency.
In parts of northern England, Northern Ireland and Scotland, 'get' is still used in preference to 'git'.
The word has been ruled by the Speaker of the House of Commons to be unparliamentary language.