Calms notedly rough seas (5)
I believe the answer is:
eases
'calms' is the definition.
(I've seen this before)
'notedly rough seas' is the wordplay.
'notedly' becomes 'e' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'rough' is an anagram indicator.
'seas' anagrammed gives 'ases'.
'e'+'ases'='EASES'
Can you help me to learn more?
(Other definitions for eases that I've seen before include "provides relief" , "Softens" , "Relieves, lightens" , "Assuages or slackens" , "Facilitates" .)