If you moor a boat [or if you moor], you stop in a place and tie a/the boat up to the land, a dock, buoy or some other place with a rope or cable so that it cannot drift away.
To me 'moor' seems to need something after it. In other words we don't just 'moor', we 'moor something'. Granted, I grew up far from the sea, so it may be different for others.
Interested in Language