Gas masks are impermeable only to certain kinds of gas.
Useful english dictionary. 2012.
per|cep´ti|bly — per|cep|ti|ble «puhr SEHP tuh buhl», adjective. that can be perceived; observable; appreciable: »a perceptible improvement, a perceptible time. The other ship was barely perceptible in the fog. SYNONYM(S): palpable, cognizable.… … Useful english dictionary
per´me|a|bly — per|me|a|ble «PUR mee uh buhl», adjective. that can be permeated; allowing the passage or diffusion of liquids or gases through it: »permeable cell walls. A sponge is permeable by water. SYNONYM(S): pervious. ╂[< Latin permeābilis <… … Useful english dictionary
per|mis´si|bly — per|mis|si|ble «puhr MIHS uh buhl», adjective. that can be permitted; allowable. SYNONYM(S): admissible. –per|mis´si|ble|ness, noun. –per|mis´si|bly, adverb … Useful english dictionary
per|ceiv´a|bly — per|ceiv|a|ble «puhr SEE vuh buhl», adjective. that can be perceived; perceptible. SYNONYM(S): intelligible, appreciable. –per|ceiv´a|bly, adverb … Useful english dictionary
per|du|ra|bly — «puhr DUR uh blee, DYUR », adverb. in a perdurable manner; permanently … Useful english dictionary
im´per|cep´ti|bly — im|per|cep|ti|ble «IHM puhr SEHP tuh buhl», adjective. 1. very slight; gradual: »The road took an imperceptible rise over the low hill. 2. that cannot be perceived or felt; subtle or indistinct: »There were imperceptible differences between the… … Useful english dictionary
im|per´ish|a|bly — im|per|ish|a|ble «ihm PEHR ih shuh buhl», adjective. not perishable; unable to be destroyed; lasting forever; enduring; indestructible: »But in contentment I still feel the need of some imperishable bliss (Wallace Stevens). SYNONYM(S): immortal.… … Useful english dictionary
im´per|turb´a|bly — im|per|turb|a|ble «IHM puhr TUR buh buhl», adjective. not easily excited or disturbed; calm: »A man…Cool, and quite English, imperturbable (Byron). –im´per|turb´a|ble|ness, noun. –im´per|turb´a|bly, adverb … Useful english dictionary
im´per|mis´si|bly — im|per|mis|si|ble «IHM puhr MIHS uh buhl», adjective. not permissible »But there is that line between the permissible and the impermissible in demagoguery (Harper s). –im´per|mis´si|bly, adverb … Useful english dictionary
su|per|sen|si|bly — «SOO puhr SEHN suh blee», adverb. in a supersensible manner … Useful english dictionary
