Leach, v. t. [imp. & p. p.Leached (?); p. pr. & vb. n.Leaching.] [Written also leech and letch.] 1. To remove the soluble constituents from by subjecting to the action of percolating water or other liquid; as, to leach ashes or coffee.
2. To dissolve out; — often used with out; as, to leach out alkali from ashes.