Lived with Ted, perhaps, but was lost on him (3)

I believe the answer is:

was

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But I can't explain it at all! Could you help me understand?

(Other definitions for was that I've seen before include "Existed in the past" , "Lived" , "(I/he) existed" , "(I/he/she/it) existed" , "Is no longer" .)

I've seen this clue in the Evening Standard.

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