in Gedanken

lost in thought

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phrase Rare #49,843

lost in thought Often describes someone who is distracted or absorbed in their thoughts.

GE: Sie saß am Fenster und war in Gedanken.

EN: She sat by the window, lost in thought.

Er war in Gedanken versunken.

He was lost in thought.

Ich war wohl in Gedanken.

I was probably lost in thought.

— State and Main (2000)

Er war immer in Gedanken, nur fanden wir nie raus, in welchen.

He was always on our minds, but we never found out which ones.

— Alles eine Frage der Zeit (2013)