Old-fashioned but popular with the boys (5)

I believe the answer is:

dated

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'old-fashioned' is the definition.
(I've seen this in another clue)

I cannot understand how the remainder of the clue works.

(Other definitions for dated that I've seen before include "Old fashioned" , "Rusty" , "Outmoded" , "Passe" , "Went out with - old hat" .)

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

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