\Im*pros"per*ous\, a. [Pref. im- not + prosperous:
cf. F. improsp[`e]re, L. improsper.]
Not prosperous. [Obs.] --Dryden. -- {Im*pros"per*ous*ly},
adv. [Obs.] -- {Im*pros"per*ous*ness}, n. [Obs.]