Laches \Lach"es\ (l[a^]sh"[e^]z), Lache \Lache\ (l[a^]sh), n. [OF. lachesse, fr. lache lax, indolent, F. l[^a]che, ultimately fr. L. laxus loose, lax. See {Lax}.] (Law) Neglect; negligence; remissness; neglect to do a thing at the proper time; especially, a delay in asserting a claim, sufficient to cause a person to lose the right to adjuducation of the claim by a court.
It ill became him to take advantage of such a laches with the eagerness of a shrewd attorney. --Macaulay.
Patent lawyers also say that, in any suits, clone makers would be able to invoke a legal principle called laches.