hys‧ter‧ics /hɪˈsterɪks/ noun [plural] spoken

1. when you are unable to control your behaviour or emotions because you are very upset, afraid, excited etc:
She went into hysterics when she heard about her husband.
have hysterics British English (=be extremely upset or angry)
Mum’d have hysterics if she knew what you’d done.

2. in hysterics if someone is in hysterics, they are laughing and not able to stop:
The audience was in hysterics.

[TahlilGaran] Dictionary of Contemporary English ▲