An archaic or dialectal adverb meaning 'in a reek' or 'smoking', now obsolete.
From 'a' (on, in) + 'reek' (smoke, steam). A Middle English construction that fell out of use as grammar evolved.
Areek preserves how English once worked—adjectives and adverbs were built by prefixing 'a-' to nouns or adjectives, a pattern that mostly disappeared by the Renaissance!
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