Studied a small river entering sea? (8)
I believe the answer is:
measured
'studied' is the definition.
(thesaurus)
'a small river entering sea?' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'river' becomes 'ure' (river in Yorkshire).
'entering' is an insertion indicator.
'sea?' becomes 'med' (abbreviation of Mediterranean).
'a'+'s'+'ure'='asure'
'asure' going inside 'med' is 'MEASURED'.
(Other definitions for measured that I've seen before include "Calculated, quantified" , "Dare Muse be regular in movement" , "Carefully considered - armed use (anag)" , "Having a slow and regular rhythm" , "Regular in movement or carefully considered" .)