In a manner that is answerable; in a way that can be answered or in proportion to something else.
Formed from answerable plus the adverb suffix -ly, which comes from Old English -lice, meaning 'in the manner of' or 'resembling.'
The word 'answerable' originally meant 'proportionate' or 'corresponding to'—so answerably can mean 'in a way that corresponds or matches,' a meaning that predates the modern sense of 'able to be answered'!
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