to cancel plans, dates or events

To give the cold shoulder to someone considered a nuisance or want nothing to do with.

1.) To tell someone to go away in a rude manner.


2.) To shine on, or to ignore

British slang for farting.which is far different from the American meaning: to ignore, avoid, dumping of a girlfriend or boyfriend

Blow off is a British slang term usually used by children to mean "fart". This term was prevalent up until recently but its use seems to be declining and the bawdy American version which means to ignore, or snub, is taking over.
This is one of the reasons Americans are laughed at in Britain as it causes some humour in British households.

- to give a blow job

in poker, blow off means to loose money being careless and stupid