An ancient Greek coin worth two obols; another form of diobol.
From Greek 'di-' (two) + 'obolos' (obol) + suffix '-on,' the Greek diminutive or standard nominative ending, documented in ancient numismatic texts.
The ending '-on' in ancient Greek often creates a kind of masculine or diminutive form, and you see the same pattern in words like 'electron' and 'helicon'—it's a fascinating Greek grammatical feature that English borrowed wholesale for scientific terms.
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