Like serene seas (4)
I believe the answer is:
calm
(Other definitions for calm that I've seen before include "Absence of wind" , "'Tranquil, placid (4)'" , "Still and quiet" , "Halcyon" , "Serene" .)
I believe the answer is:
calm
(Other definitions for calm that I've seen before include "Absence of wind" , "'Tranquil, placid (4)'" , "Still and quiet" , "Halcyon" , "Serene" .)