Example: "A soundproof room"
Example: "Proust had his apartment soundproofed"
Something that prevents sound from traveling through it, such as is put on walls so adjacent areas are not disturbed by noise.
Example: "Until the soundproofing is installed, i don't think i'll be able to get to sleep here."
The act of installing material to dampen sound.
Example: "The soundproofing will take place today."