Where ocean silt spreads? (9)

I believe the answer is:

coastline

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'where ocean silt spreads?' is the definition.
The answer is a location as well as being a singular noun. This is suggested by the definition.

'where ocean silt' is the wordplay.
'where' is an anagram indicator (I've seen this in other clues).
'ocean'+'silt'='oceansilt'
'oceansilt' anagrammed gives 'COASTLINE'.

Can you help me to learn more?

(Other definitions for coastline that I've seen before include "Shore boundary" , "Sea margin" , "Shape of the seashore" , "21 [SEASIDE]" , "Edge of a landmass" .)

I've seen this clue in The Daily Mail.

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