What does "boss" mean?

Boss: 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.

Additional senses

  1. 2.(Arch.) A projecting ornament placed at the intersection of the ribs of ceilings, whether vaulted or flat, and in other situations.
  2. 3.Etym: [Cf. D. bus box, Dan. bösse.] 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. Gwilt.
  3. 4.(Mech.) (a) The enlarged part of a shaft, on which a wheel is keyed, or at the end, where it is coupled to another. (b) A swage or die used for shaping metals.
  4. 5.A head or reservoir of water. [Obs.]
  5. 6.To ornament with bosses; to stud.
  6. 7.A master workman or superintendent; a director or manager; a political dictator. [Slang, U. S.]

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