In a manner showing reluctance or resistance; without wanting to do something.
From 'un-' (not) + 'willing' + '-ly' (adverb suffix). All three components have Old English roots, creating a word that means 'not in a willing manner.'
The 'un-' prefix is so powerful in English that we can attach it to almost any adjective to create its opposite—'unwillingly' shows how flexible English is at creating new meanings from simple building blocks!
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