The quality, state, or property of running or flowing downward; a downward process or current.
From Latin 'decurrens' (running down), formed by combining 'de-' (down) and 'currere' (to run), with the English '-cy' suffix to denote a state or quality.
Just as 'currency' relates to things flowing (like money flowing through an economy), 'decurrency' specifically means things flowing down—it's a word designed perfectly to describe gravity and water, but nobody uses it anymore!
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