\Lach"es\, Lache \Lache\, 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; delay to assert a claim.
      It ill became him to take advantage of such a laches
      with the eagerness of a shrewd attorney. --Macaulay.