11 letters · 12 points in Scrabble
adjective harmful to living things
originAdapted borrowing (1640s; 1582 as deletorious) of New Latin dēlētērius, dēlētōrius + -ous, from Ancient Greek δηλητήριος (dēlētḗrios, “noxious, deleterious”), from δηλητήρ (dēlētḗr, “a destroyer”), from δηλέομαι (dēléomai, “I hurt, damage, spoil, waste”). Not related to delete or deleble. Doublet of deletery.
Etymology from Wiktionary, CC BY-SA 3.0