Word Origin & History
leak"to let water in or out" [Johnson], 1420, from M.Du. leken "to drip, to leak," or from O.N. leka, cognate of O.E. leccan "to moisten" (which did not survive into M.E.), all from P.Gmc. *lek- "deficiency" (cf. O.H.G. lecchen "to become dry," Ger. lechzen "to be parched with thirst"). The noun is from
1487. The figurative meaning "come to be known in spite of efforts at concealment" dates from at least 1832; transitive sense first recorded 1859; the noun in this sense dates from 1950. Noun sense of "act of urination" is from 1934 (first attested in "Tropic of Cancer"); but the verb meaning "to piss" is from 1596.
"Why, you will allow vs ne're a Iourden, and then we leake in your Chimney." ["I Hen. IV," II.i.22]