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Study Dictionary
Despair
DESPAIR [ISBE]
DESPAIR - de-spar': The substantive only in 2 Cor 4:8, "perplexed, but not in (the Revised Version (British and American) "yet not unto") despair," literally, "being at a loss, but not utterly at a loss." "Unto despair" here conveys the force of the Greek prefix ex ("utterly," "out and out"). Desperate, in Job 6:26; Isa 17:11. In the latter instance, the Hebrew adjective is derived from a verb = "to be sick," and the literally, rendering would be "incurable" (compare Job 34:6, "my wound is incurable"). Desperately in Jer 17:9 the King James Version, where the heart is said to be "desperately (i.e. incurably) wicked" or "sick."
Also see definition of "Despair" in Word Study