I. adjective Date: circa 1878 impervious to sound, II. transitive verb Date: 1919 to insulate so as to obstruct the passage of sound
SOUNDPROOF
Meaning of SOUNDPROOF in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012