a. [ L. improvisus unforeseen; cf. It. improvviso. ] Not prepared or mediated beforehand; extemporaneous. [ Obs. ] Jonhson. [ 1913 Webster ]

n.; pl. Provisos [ L., (it) being provided, abl. of provisus, p. p. of providere. See Provide, and cf. Purview. ] An article or clause in any statute, agreement, contract, grant, or other writing, by which a condition is introduced, usually beginning with the word provided; a conditional stipulation that affects an agreement, contract, law, grant, or the like; as, the contract was impaired by its proviso. [ 1913 Webster ]

He doth deny his prisoners,
But with proviso and exception. Shak. [ 1913 Webster ]

n. [ L., fr. providere: cf. F. proviseur. See Provide. ] 1. One who provides; a purveyor. [ Obs. ] “The chief provisor of our horse.” Ford. [ 1913 Webster ]

2. (R. C. Ch.) (a) The purveyor, steward, or treasurer of a religious house. Cowell. (b) One who is regularly inducted into a benefice. See Provision, 5. P. Plowman. [ 1913 Webster ]

3. (Eng. Hist.) One who procures or receives a papal provision. See Provision, 6. [ 1913 Webster ]

adv. In a provisory manner; conditionally; subject to a proviso; as, to admit a doctrine provisorily. Sir W. Hamilton. [ 1913 Webster ]

n. The office or position of a provisor. [ R. ] J. Webster. [ 1913 Webster ]

a. [ Cf. F. provisoire. ] 1. Of the nature of a proviso; containing a proviso or condition; conditional; as, a provisory clause. [ 1913 Webster ]

2. Making temporary provision; provisional. [ 1913 Webster ]