Apparently from yabal (compare ybuwl) and Qayin; offspring of Cain; Tubal-Kajin, an antidiluvian patriarch -- Tubal-cain.
see HEBREW yabal
see HEBREW ybuwl
see HEBREW Qayin
H8424. tugah
תּוּגָה noun feminine grief (poetry) — absolute ׳ת Psalm 119:28; Proverbs 14:13; 17:21; construct תּוּגַת 10:1; — grief Psalm 119:28; Proverbs 10:1 (opposed to יְשַׂמַּח), 14:13 (opposed to שִׂמְחָה), 17:21 ("" יִשְׂמַח לֹא).