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Study Dictionary
Painfulness
PAINFULNESS [ISBE]
PAINFULNESS - pan'-fool-nes (mochthos): In the summary of his missionary labors in 2 Cor 11:27 the King James Version, Paul uses this word. The Revised Version (British and American) renders it "travail," which probably now expresses its meaning more closely, as in modern usage "painfulness" is usually restricted to the condition of actual soreness or suffering, although we still use "painstaking" in the sense of careful labor. The Greek word is used for toil or excessive anxiety, as in Euripides (Medea, 126), where it refers to that care for her children which she had lost in her madness. Tyndale uses "painfulness" in 1 Jn 4:18 as the translation of kolasis, which the King James Version renders "torment" and the Revised Version (British and American) "punishment."Alexander Macalister
Also see definition of "Painfulness" in Word Study