Some potion said to mean a lot of water (5)
I believe the answer is:
ocean
'water' is the definition.
(I know that ocean is a type of water)
'some potion said to mean a lot of' is the wordplay.
I cannot really see how this works, but
'some' could be 'a' and 'a' is found within the answer.
'lot' could be 'c' and 'c' is found within the answer.
'of' could be 'o' and 'o' is present in the answer.
The remaining letters 'en' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for ocean that I've seen before include "It's pretty wet!" , "Large expanse of sea" , "tons of water" , "eg Indian, Atlantic" , "Vast sea" .)