To reduce in quantity or amount; to diminish the amount or number of something.
From dis- (reversal, away) + quantity (from Latin quantitas, how much). This is a rare or obsolete formation using dis- as a prefix to create a reverse action.
This ultra-rare word shows how productive the dis- prefix is—you can theoretically dis- almost any noun or adjective to reverse it, though most combinations never catch on. 'Disquantity' died out because 'reduce' or 'diminish' were simpler.
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