Synonyms for Bollard:

n.

flotation device, life jacket, buoy, lifebelt, life preserver, anchor, blade, inboard motor, ballast. bollard (noun)
bitt.

Other synonyms:

life preserver, lifebelt, flotation device, ballast, life jacket, inboard motor. buoy. anchor, blade. Other relevant words:
anchor, ballast, blade, buoy, lifebelt.