crack_up has definitions from the field of medicine
1
[ verb ] (medicine) suffer a nervous breakdown

Used in print

(Charles Glicksberg, "Sex in Contemporary Literature"...)

One beatnik got the woman he was living with so involved in drugs and self-analysis and all-night sessions of sex that she was beginning to crack_up .

Related terms

suffer collapse

2
[ verb ] rhapsodize about

Related terms

laud

3
[ verb ] laugh unrestrainedly

Synonyms

break_up

Related terms

laugh

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