Gains power over turbulent streams (7)
I believe the answer is:
masters
'gains power' is the definition.
The definition and answer can be both related to competing as well as being verbs in their -s form.
Maybe they are linked in a way I don't understand?
'turbulent streams' is the wordplay.
'turbulent' indicates anagramming the letters.
'streams' anagrammed gives 'MASTERS'.
'over' acts as a link.
Can you help me to learn more?
(Other definitions for masters that I've seen before include "Male teachers" , "Could be checkers" , "Boys" , "competition today" , "Artists of consummate skill" .)