criser

Criser is a very informal, modern verb built directly from crise — to have a meltdown, freak out, or throw a fit (elle a crisé quand elle a vu la note). It's everyday spoken French, especially among younger speakers, not something you'd write formally.

• Il a crisé quand il a vu le prix. — He freaked out when he saw the price.
• Ne crise pas, on va trouver une solution. — Don't freak out, we'll find a solution.
• Elle crise dès que son frère touche à ses affaires. — She loses it the moment her brother touches her stuff.

Criser is casual slang and won't appear in formal writing or textbooks as often as its meaning would suggest — avoir une crise or paniquer is the safer, more neutral choice outside informal conversation.