Old English sot "soot," from Proto-Germanic *sotam "soot" (source also of Old Norse sot, Old Dutch soet, North Frisian sutt), literally "what settles," from PIE *sodo- (source also of Old Church Slavonic sažda, Lithuanian suodžiai, Old Irish suide, Breton huzel "soot"), suffixed form of root *sed- (1) "to sit."
adjective suffix, "full of or characterized by," from Old English -ig, from Proto-Germanic *-iga- (source also of Dutch, Danish, German -ig, Gothic -egs), from PIE -(i)ko-, adjectival suffix, cognate with elements in Greek -ikos, Latin -icus (see -ic). Originally added to nouns in Old English; used from 13c. with verbs, and by 15c. even with other adjectives (for example crispy).
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Definitions of sooty
of the blackest black; similar to the color of jet or coal;