Defn: The quality of being impermeable.
IMPERMEABLE Im*per"me*a*ble, a. Etym: [Pref. im- not + permeable: cf. F. imperméable, L. impermeabilis.]
Defn: Not permeable; not permitting passage, as of a fluid. through its substance; impervious; impenetrable; as, India rubber is impermeable to water and to air. — Im*per"me*a*ble*ness, n. — Im*per"me*a*bly, adv.
IMPERMISSIBLE
Im`per*mis"si*ble, a.
Defn: Not permissible.
IMPERSCRUTABLE
Im`per*scru"ta*ble, a. Etym: [L. imperscrutabilis.]
Defn: Not capable of being searched out; inscrutable. [Obs.] —
Im`per*scru"ta*ble*ness, n. [Obs.]
IMPERSEVERANT
Im`per*sev"er*ant, a.
Defn: Not persevering; fickle; thoughtless. [Obs.]
IMPERSONAL Im*per"son*al, a. Etym: [L. impersonalis; pref. im- not + personalis personal: cf. F. impersonnel. See Personal.]