In a way that is extremely offensive, revolting, or repulsive to the senses or morals.
From 'disgusting,' which comes from 'disgust' (Old French 'desgouster'—to turn away from due to bad taste), with the suffix '-ly' added to create an adverb form. The '-ing' form adds the sense of causing disgust.
The word 'disgust' actually originates from taste—literally 'de-' (away from) + 'gout' (taste)—so when you're disgusted, you're experiencing a visceral reaction that evolved to protect us from eating poison; that's why disgust feels so physically immediate.
Complete word intelligence in one call. Free tier — 50 lookups/day.