What does "costive" mean?

Costive: Reserved; formal; close; cold. [Obs.] "A costive brain." Prior. "Costive of laughter." B. Jonson. You must be frank, but without indiscretion; and close, but without being costive. Lord Chesterfield.

Additional senses

  1. 2.Dry and hard; impermeable; unyielding. [Obs.] Clay in dry seasons is costive, hardening with the sun and wind. Mortimer.

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