An archaic or obsolete term, possibly a variant of 'beeswax' or 'beetle', or perhaps a dental term in Middle English.
Uncertain origin, but possibly from Old English roots related to 'beet' (beetle) or 'bēo' (bee), with the '-th' ending suggesting an abstract noun or archaic formation.
Sometimes the hardest words to understand are the abandoned ones—'beeth' appears in a few old texts but its meaning was so specialized or regional that it vanished before lexicographers could pin it down.
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