Water at the mouth (5)
I believe this is a double definition.
'water' is the first definition.
(I know that estuary is a type of water)
'the mouth' is the second definition.
(I've seen this before)
'at' is the link.
(Other definitions for estuary that I've seen before include "form of English" , "Here one comes close to the main" , "eg Thames, Humber" , "Wide part of a river where it nears the sea" , "route to sea" .)
This could be a double definition.
'water' is the first definition.
The definition and answer can be both natural objects as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'the mouth' is the second definition.
(I've seen this before)
'at' acts as a link.
Can you help me to learn more?
(Other definitions for delta that I've seen before include "Area where a river divides before entering the sea" , "Eg, outlet of the Nile" , "The fourth Greek letter found at river's mouth" , "Silted estuary" , "Mouth of, eg, the Nile" .)