[1] : The Collaborative International Dictionary of English v.0.48

laches \lach"es\ la^sh"e^z, lache \lache\ la^sh, n.
   of. lachesse, fr. lache lax, indolent, f. l^ache,
   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.
   1913 webster

         it ill became him to take advantage of such a laches
         with the eagerness of a shrewd attorney. --macaulay.
   1913 webster
see also:
lax 

[2] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

laches. this word, derived from the french lecher, is nearly synonymous with 
negligence. 
     2. in general, when a party has been guilty of laches in enforcing his 
right by great delay and lapse of time, this circumstance will at common law 
prejudice, and sometimes operate in bar of a remedy which it is 
discretionary and not compulsory in the court to afford. in courts of 
equity, also delay will generally prejudice. 1 chit. pr. 786, and the cases 
there cited; 8 com. dig. 684; 6 johns. ch. r. 360. 
     3. but laches may be excused from, ignorance of the party's rights; 2 
mer. r. 362; 2 ball  beat. 104; from the obscurity of the transaction; 2 
sch.  lef. 487; by the pendancy of a suit; 1 sch.  lef. 413; and where the 
party labors under a legal disability, as insanity, coverture, infancy, and 
the like. and no laches can be imputed to the public. 4 mass. rep. 522; 3 
serg.  rawle, 291; 4 hen.  munf. 57; 1 penna. r. 476. vide 1 supp. to 
ves. jr. 436; 2 id. 170; dane's ab. index, h.t.; 4 bouv. inst. n. 3911. 

Laches >> L Words
Laches, definition of term: Laches
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