Weapon left on a liner below dock (7)
I believe the answer is:
cutlass
'weapon' is the definition.
(cutlass is a kind of weapon)
'left on a liner below dock' is the wordplay.
'left on a liner' becomes 'lass' (I can't explain this - if you can you should believe this answer much more).
'below' says to put letters next to each other (in a down clue, some letters go below others).
'dock' becomes 'cut'.
'lass' put after 'cut' is 'CUTLASS'.
Can you help me to learn more?
(Other definitions for cutlass that I've seen before include "Pirate's weapon" , "Short, heavy curved sword" , "Pirate's sword" , "Curved sailors' sword" , "Old sailor's weapon" .)