[noun] [C] - a very young catOur cat has just had six kittens.If you say that someone is having kittens (US also having a cow), you mean that they are very worried, upset or angry about something.My mother nearly had kittens when I said I was going to buy a motorbike.
KITTEN
Meaning of KITTEN in English
Cambridge English vocab. Кембриджский английский словарь. 2012