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Study Dictionary
Decay
DECAY [ISBE]
DECAY - de-ka': Although this word is still in good use in both its literal sense, of the putrefaction of either animal or vegetable matter, and its derived sense, denoting any deterioration, decline or gradual failure, the Revised Version (British and American) has replaced it by other expressions in Lev 25:35; Eccl 10:18; Isa 44:26; Heb 8:13; in some of these cases with a gain in accuracy of translation. In Neh 4:10 (kashal, "to be feeble," "stumble") the Revised Version (British and American) retains "is decayed"; in Job 14:11 (charebh, "to be dried up") the American Standard Revised Version substitutes "wasteth," and in Jn 11:39 the American Standard Revised Version has "the body decayeth" instead of the more literal translation offensive to modern ears (ozei, "emits a smell").F. K. Farr
Also see definition of "Decay" in Word Study