Lexical Definition

‎כָּסַל‎ kâçal (kaw-sal') be stupid H:V
a primitive root

be foolish.

1) (Qal) to be foolish, be stupid

Usage: 1 form in 1 verse
Form Translated As     In Verse(s)
וְיִכְסָ֑לוּ and they may be foolish Jer.10.8

Brown-Driver-Briggs

[‎כָסַל‎] verb be or become stupid (Late Hebrew Aramaic in derivatives; Arabic be sluggish, so North Syriac in derivatives; original meaning possibly thick, plump, fat; hence in good sense: ‎כְּסָלִים‎ loins, ‎כֶּסֶל‎, ‎כִּסְלָה‎ confidence; in bad sense: ‎כֶּסֶל‎, ‎כִּסְלָה‎, ‎כְּסִילוּת‎ stupidity, folly, ‎כְּסִיל‎ stupid fellow) —

Qal Imperfect ‎יִכְסָ֑לוּ‎ they become stupid Jer 10:8 (|| ‎יִבְעֲרוּ‎ they become brutish).

Brown-Driver-Briggs References

Book Refs
Jeremiah 10:8