Used to be misused by Ted (3)

I believe the answer is:

was

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'used to be' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

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

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