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Webster 1913 Edition
Improsperous
Im-pros′per-ous
,Adj.
[Pref.
im-
not + prosperous
: cf. F. improspère
, L. improsper
.] Not prosperous.
[Obs.]
Dryden.
– Im-pros′per-ous-ly
, adv.
[Obs.]
– Im-pros′per-ous-ness
, Noun.
[Obs.]
Webster 1828 Edition
Improsperous
IMPROS'PEROUS
,Adj.
[Unprosperous is the word most generally used in the sense.]