Leakproof means made so that nothing can escape. A leakproof lid, leakproof seals, guaranteed leakproof.
It is a stronger claim than leak-resistant, and manufacturers choose between the two words carefully. A leakproof container has to be sealed at the joint rather than merely covered, and the test is usually turning it upside down with water in it.
1adjectiveleakproofMade so that nothing can escape.
“Pack the soup in a leakproof container so it doesn't spill in your bag.”
leakproof is a quality.
Proto-Indo-European
*leg- — to leak
Proto-Germanic
*lekaną — to leak, drain
Old Norse
leka — to leak, drip
Middle Dutch
leken — to leak, drip
Old English
*lecan — to leak
Middle English
leken — to let water in or out
English
leak
English, today
leakproof
From leak + -proof. leak comes from Middle English leken (“to let water in or out”), from Old English lecan (“to leak”), Middle Dutch leken (“to leak, drip”) or Old Norse leka (“to leak, drip”); all from Proto-Germanic lekaną (“to leak, drain”), from Proto-Indo-European leg- (“to leak”). Cognate with Dutch lekken (“to leak”), German lechen, lecken (“to leak”), Danish lække (“to leak”), Swedish läcka (“to leak”), Norwegian Bokmål lekke (“to leak”), Faroese, Icelandic and Norwegian Nynorsk leka (“to leak”). Related also to Old English leċċan (“to water, wet”), Albanian lag, lak (“to damp, make wet”). See also leach, lake. divulgation, disclosure of information Compare typologically изтичане, przeciek, уте́чка (akin to течь).
Etymology from Wiktionary, CC BY-SA