From yada'; knowledge -- knowledge, opinion.
see HEBREW yada'
H1843. dea
[דֵּעַ] noun [masculine] knowledge, opinion (late) — only suffix דֵּעִי Job 32:6 3t., and plural דֵּעִים 37:6; all in speech of Elihu.
1 knowledge, ד ׳תְּמִים Job 37:16 one perfect in knowledge (of God).
2 judgement, opinion Job 36:3; דֵּעִי חַֹוּת 32:6 to declare my opinion, so 32:10; 32:17.