One-time or one time (4)

I believe the answer is:

once

This clue is a double definition.

'one-time' is the first definition.

'one time' is the second definition.
(synonyms)

'or' is the link.

(Other definitions for once that I've seen before include "In the old days" , "Formerly; as soon as" , "Singly" , "in bygone days" , "On one occasion" .)

I've seen this clue in The Telegraph and The Globe and Mail.

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