Breakwater (6)

'breakwater' is the definition.
(I know that breakwater can be written as groyne)
This is the entire clue.
(Other definitions for groyne that I've seen before include "A bulwark" , "Structure built to control coastal erosion" , "Protective wall extending into water" , "Sea wall" , "Anti-erosion breakwater" .)
'breakwater' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for pier that I've seen before include "Seaside attraction" , "Buttress; landing place" , "sight at the seaside" , "Ripe as a jetty (4)" , "seaside building" .)
'breakwater' is the definition.
(I know that breakwater can be written as mole)
This is the entire clue.
(Other definitions for mole that I've seen before include "Adrian ---, fancies Pandora; lurking spy" , "Counterspy" , "Furry burrowing animal" , "Agent; breakwater" , "Jetty; animal" .)