What does "sergeant" mean?

Additional senses

1. 2.(Mil.) In a company, battery, or troop, a noncommissioned officer next in rank above a corporal, whose duty is to instruct recruits in discipline, to form the ranks, etc. Note: In the United States service, besides the sergeants belonging to the companies there are, in each regiment, a sergeant major, who is the chief noncommissioned officer, and has important duties as the assistant to the adjutant; a quartermaster sergeant, who assists the quartermaster; a color sergeant, who carries the colors; and a commissary sergeant, who assists in the care and distribution of the stores. Ordnance sergeants have charge of the ammunition at military posts.
2. 3.(Law) A lawyer of the highest rank, answering to the doctor of the civil law; -- called also serjeant at law. [Eng.] Blackstone.
3. 4.A title sometimes given to the servants of the sovereign; as, sergeant surgeon, that is, a servant, or attendant, surgeon. [Eng.]
4. 5.(Zoöl.) The cobia. Drill sergeant. (Mil.) See under Drill. -- Sergeant-at-arms, an officer of a legislative body, or of a deliberative or judicial assembly, who executes commands in preserving order and arresting offenders. See Sergeant, 1. -- Sergeant major. (a) (Mil.) See the Note under def. 2, above. (b) (Zoöl.) The cow pilot.