gas-proof1
/ˈɡaspruːf/adjective
Impermeable to (especially poisonous) gas; gas-tight.
Origin
Mid 19th century; earliest use found in Boston Daily Atlas. From gas + proof.
gas-proof2
/ˈɡaspruːf/verb
[with object] To make (an enclosure, material, etc.) gas-proof.
Origin
Mid 19th century. From gas-proof.