Etymology: First recorded late in 15th cent.; the proximate source is uncertain; perhaps, like many other nautical terms, adopted < Low German or Dutch; compare Low German, Middle Dutch lek, inflected lēk- (whence German leck, Danish læk; the German lecke, Swedish läcka are < the verb), Dutch lek; equivalent forms are German dialect lech, leche, Old Norse leke strong masculine. It is possible that the English word, notwithstanding its late appearance, may represent an adoption of the Old Norse form, or even an Old English cognate. The exact relation between the noun and the adjective and verb is undetermined.

Etymology: In Old English hlec ; after Old English the word does not appear until the 16th cent. when it may have been adopted < Low German, Middle Dutch lek (inflected lēk- ), whence modern Dutch lek , Swedish läck , Danish læk , German leck ; cognate with Old Norse lekr , German dialect lech of the same meaning, and with leak n., leak v.The Old English form presents difficulties; the spelling hlec occurs in the Hatton MS. of the Pastoral Care (9th cent.) and in at least three glosses, so that it cannot well be a mere error; on the other hand the (apparently) cognate words in the other Germanic languages show no trace of the h; in the Old Norse verb leka the initial l (not hl) is attested by the alliteration.

Etymology: Not found before c1420, but probably much older; < or cognate with Old Norse leka strong verb (past tense lak ) to drip, to leak, corresponding to Old High German *lechen strong verb, found only in compounds (past participle zelechen leaky), Middle High German and dialect modern German lechen weak, to crack from drought, become leaky, Middle Dutch leken (past tense lak ) to let water through, drip; < Germanic root *lek- , ablaut variant of *lak- : see lack adj.It is very likely that in later use the verb was formed afresh < leak n. or leak adj. Sense 5 may be plausibly explained as a development from sense 2, but it is not wholly impossible that it may be a distinct word, a variant of leach v.², Old English lęccan . The Low German lecken (whence Swedish läcka , Danish lække , German lecken ) is derived from, or at least refashioned after, the equivalent of leak adj. or leak n.