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Im*prov"i*sate (?), a. [See Improvise.]
Unpremeditated; impromptu; extempore.
© Webster 1913.
Im*prov"i*sate (?), v. t. & i. [imp. & p. p. Improvisated (?); p. pr. & vb. n. Improvisating (?).]
To improvise; to extemporize.