Standard feature of Saturn or Mars (4)

I believe the answer is:

norm

'standard' is the definition.
(I know that norm is a type of standard)

'feature of saturn or mars' is the wordplay.
'feature of' says the answer is hidden in the clue.
'NORM' is hidden within 'saturn or mars'.

(Other definitions for norm that I've seen before include "Mean" , "Standard regarded as typical" , "expected thing" , "Bacterium, virus, etc" , "What is conventional, regular" .)

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

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