From kacal; properly, fatness, i.e. By implication (literally) the loin (as the seat of the leaf fat) or (generally) the viscera; also (figuratively) silliness or (in a good sense) trust -- confidence, flank, folly, hope, loin.
see HEBREW kacal
H3689. kesel
כֶּ֫סֶל noun masculine
1 loins,
2 stupidity,
3 confidence (Late Hebrew id. lion; Aramaic כִּסְלָא id.); —
1 loins כָּ֑סֶל Job 15:27; plural כְּסָלִים Leviticus 3:4, 10, 15; 4:9; 7:4; suffix כְּסָלַי, Psalm 38:8.
2 stupidity, folly ׳כ Ecclesiastes 7:25 ("" סִכְלוּת), כֵּסֶל Psalm 49:14.
3 confidence, suffix כִּסְלִי Job 31:24; כִּסְלֶ֑ךָ Proverbs 3:26; כִּסְלוֺ Job 8:14; כִּסְלָם Psalm 78:7.