Tie at the dock (4)
I believe the answer is:
moor
'tie at the dock' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for moor that I've seen before include "Upland area - tie up" , "Old North African" , "Anchor" , "Securely fix" , "North African - secure a boat - tract of land" .)