Increase a nutmeg order (7)
I believe the answer is:
augment
'increase' is the definition.
(I know that augment is a more specific form of the action increase)
'a nutmeg order' is the wordplay.
'order' indicates anagramming the letters.
'nutmeg' is an anagram of 'ugment'.
'a'+'ugment'='AUGMENT'
(Other definitions for augment that I've seen before include "Increase number of" , "Make greater in size, number, etc." , "Enlarge or increase" , "Add to, increase" , "boost" .)