МОЗГИ ВАРЯТ

• ГОЛОВА ВАРИТ (у кого) coll; КОТЕЛОК ВАРИТ substand; МОЗГИ ВАРЯТ substand

[VPsubj; usu. this WO]

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1. s.o. is bright, intelligent: у X-a голова <котелок> варит ≈ X has a good head on his shoulders; X's head is screwed on straight; X has a lot <X is really> on the ball; X is one smart cookie; X has (the) smarts; X has brains.

2. [neg only]

⇒ s.o. cannot think clearly (because of fatigue, illness etc):

- у X-a голова не варит••≈ X can't think straight;

- X's brain refuses to function;

- X's brain is on the blink;

- X's brain is mush (fried).