the.com/ill

One letter from 'ill-fated,' several steps from 'fine,' and everyone knows which one you mean.

means Sick, unwell, or — in slang flipped on its head — impressively good.

from From Old Norse 'illr,' meaning bad or evil, which arrived with Norse settlers and elbowed its way into English to mean sick or harmful. The slang reversal — 'ill' as a compliment, meaning excellent or skillful — emerged much later in hip-hop and street vernacular, following the same flip-the-insult-into-praise logic as 'bad' meaning 'good.'

origin
from Old Norse illr, meaning bad or wicked
slang flip
in hip-hop, ill means excellent, not sick
euphemism king
used to avoid saying the actual diagnosis
grammar trap
ill becomes illness, not illity
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