Strengthen the coastline (5)
I believe the answer is:
shore
This could be a double definition.
'strengthen' is the first definition.
Although both the answer and definition are verbs in their base form, I don't understand how they can define each other.
'the coastline' is the second definition.
(I've seen this in another clue)
Can you help me to learn more?
(Other definitions for shore that I've seen before include "Stay in" , "Seafront" , "Beam" , "Land by water" , "Horse (anag.)" .)