Vast expanse of water (5)
I believe the answer is:
ocean
(Other definitions for ocean that I've seen before include "Great sea" , "Huge expanse" , "Major sea" , "Large body of salt water" , "Large amount of water and" .)
I believe the answer is:
ocean
(Other definitions for ocean that I've seen before include "Great sea" , "Huge expanse" , "Major sea" , "Large body of salt water" , "Large amount of water and" .)