Standard measure (4)
I believe the answer is:
rule
I believe this clue is a double definition.
'standard' is the first definition.
(synonyms)
'measure' is the second definition.
(I know that rule is a type of measure)
(Other definitions for rule that I've seen before include "Control; printed line" , "Exercise power (over)" , "Govern with straight stick?" , "Control, government" , "Control using lure." .)