airtight

Adjective

airtight (comparative more airtight, superlative most airtight)

1. Impermeable to air or other gases.
   • Tupperware founder Earl Tupper in 1946 introduced its plastic products to the public, and subsequently patented their flexible airtight seal.2024 September 18, Eliza Ronalds-Hannon, “Tupperware Files for Bankruptcy Amid Declining Sales and Growing Competition”, in Time, archived from the original on 13 Dec 2024

   Synonyms:

   hermetic

2. (figuratively) Having no weak points or flaws.
   • We have an airtight argument they won’t be able to punch holes in.
   • airtight alibi
3. (figuratively) Highly reserved in some matter, particularly tight-lipped or tight-fisted.
   • when Roger asked for $100 to take the preliminary steps to establish his claim, Mike yelled like a Hebrew auctioneer, for he was air-tight and squeezed a dollar until the woman on it yelled.1908, The Plumbers Trade Journal, volume 44, Plumbers’ Trade Journal Publishing Company
   • He was ‘air-tight,’ close-mouthed, and had but few confidants or intimate friends, but numerous acquaintances.1915 April, Annals of Iowa, Historical Department of Iowa, series 3, volume 12, page 599
4. (figuratively) Triply penetrated simultaneously in the vagina, anus and mouth.