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adj. Impermeable by gas.

adj. impermeable to gases

adj. So tightly fitted as to preclude the escape of gas; impervious to gas.

Sufficiently tight to prevent the escape of gas: frequently applied to stoppers or other appliances for closing bottles, etc.

adj. not allowing air or gas to pass in or out

"The most important prerequisites. for airtight storage are gastight facilities."

tight   

airtight    watertight   

cash-stuffed    official-looking    cuendillar    serial-numbered    partially    shatra    silver-and-black    fur-bearing    quasi-official    self-addressed