in seinem Kopf

in his head

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phrase Rare #42,066
in his head Used for thoughts, mental states, or things physically located inside his head. The form changes with grammatical case; for example, “in seinen Kopf” means “into his head.”
GE: In seinem Kopf drehte sich alles um die Prüfung.
EN: In his head, everything revolved around the exam.

Ich möchte nur mal nachsehen, was so in seinem Kopf vor sich geht.

I just want to see what’s going on in his head.

— Five Nights at Freddy's 2 (2025)

Also musste er das Verbrechen auslöschen, zumindest in seinem Kopf.

So he had to erase the crime, at least in his mind.

— Psycho (1960)

Da muss etwas in seinem Kopf nicht stimmen.

There must be something wrong in his head.

— Amarcord (1973)

Er ist gestorben, weil die Knochen in seinem Kopf zerbrochen sind.

He died because the bones in his head broke.

— Die Frau im Nebel (2022)