noun a head or reservoir of water.
2. boss ·noun a swage or die used for shaping metals.
3. boss ·vt to ornament with bosses; to stud.
4. boss ·noun a master workman or superintendent; a director or manager; a political dictator.
5. boss ·noun any protuberant part; a round, swelling part or body; a knoblike process; as, a boss of wood.
6. boss ·noun the enlarged part of a shaft, on which a wheel is keyed, or at the end, where it is coupled to another.
7. boss ·noun a wooden vessel for the mortar used in tiling or masonry, hung by a hook from the laths, or from the rounds of a ladder.
8. boss ·noun a projecting ornament placed at the intersection of the ribs of ceilings, whether vaulted or flat, and in other situations.
9. boss ·noun a protuberant ornament on any work, either of different material from that of the work or of the same, as upon a buckler or bridle; a stud; a knob; the central projection of a shield. ·see umbilicus.