Definition of have (or throw) a fit in English:

have (or throw) a fit

phrase

informal
  • Be very surprised or angry.

    ‘my mother would have a fit if she heard that’
    • ‘His mother had a fit, so they married again on New Year's Day 1937, this time with the family present.’
    • ‘They were used to him throwing a fit when he was in bad mood.’
    • ‘This hardly seems like the kind of thing to be throwing a fit about.’
    • ‘Mother will be having a fit if she knows I'm sitting out in the cold air - for even though it seems warm she'll fuss.’
    • ‘If people don't want to listen to what he wants to listen to, he throws a fit.’
    • ‘I was in a line of folks standing behind a woman at the bookstore who was throwing a fit because the clerk could not find the copy of The Great Gatsby she'd called to reserve.’
    • ‘The rental company is sent away by the filming crew and my friend's husband throws a fit.’
    • ‘My mother would have a fit if she knew I spent a lot of time at Deane's.’
    • ‘You know my mother will throw a fit if she sees me like this.’
    • ‘Better get a move on so mother doesn't throw a fit when I get back.’