What does "mister" mean?

Mister: A trade, art, or occupation. [Obs.] In youth he learned had a good mester. Chaucer.

Additional senses

  1. 2.Manner; kind; sort. [Obs.] Spenser. But telleth me what mester men ye be. Chaucer.
  2. 3.Need; necessity. [Obs.] Rom. of R.
  3. 4.To be needful or of use. [Obs.] As for my name, it mistereth not to tell. Spenser.

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