In the highest degree; extremely well, or in the most important or powerful way possible.
From Latin 'supremus' (highest), related to 'super' (above). The suffix '-ly' converts it to an adverb modifying how something is done.
The word 'supremely' appears in legal documents about the 'supremacy clause' in the U.S. Constitution—it means federal law is supremely (at the highest level) more powerful than state laws.
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