Sign in trouble, ominously (3)

I believe the answer is:

leo

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'sign' is the definition.
(star sign)

I don't understand the rest of the clue.

(Other definitions for leo that I've seen before include "Lion constellation" , "Cancer, ___, Virgo" , "of pride" , "Pope" , "Man" .)

I've seen this clue in The Times and The Sun.

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