The meaning of LEAKY is permitting fluid to leak in or out. How to use leaky in a sentence. LEAKY definition: 1. Something that is leaky has a hole or crack in it that allows liquid or gas to get through: 2…. Learn more. Define leaky. leaky synonyms, leaky pronunciation, leaky translation, English dictionary definition of leaky. adj. leak·i·er , leak·i·est Permitting leaks or leakage: a leaky roof; a leaky defense system. Something that is leaky has holes, cracks, or other faults which allow liquids and gases to pass through. the cost of repairing the leaky roof. Definition of leaky adjective in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. leaky, adj. meanings, etymology, pronunciation and more in the Oxford English Dictionary leaky - WordReference English dictionary, questions, discussion and forums. All Free. LEAKY definition: allowing liquid, gas, etc., to enter or escape. See examples of leaky used in a sentence. Leaky things accidentally allow water (or gas) to pass through them. A leaky bucket is a bad thing, and a leaky diaper is even worse. LEAKY meaning: having a hole that allows something (such as a liquid or gas) to pass in or out having a leak