In a way that shows lack of skill, experience, or professionalism; done by someone who is learning or untrained.
From 'amateur' (from French 'amateur,' meaning 'lover of') plus '-ish' (expressing resemblance or degree) plus '-ly' (forming adverbs), creating a word that criticizes inexperienced execution.
Amateurishly executed work isn't always bad—some of the most creative art, music, and innovations come from people who didn't know enough to follow the 'rules' professionals insisted on.
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