Using something in small amounts or being stingy, or the act of refraining from harming someone.
From Old English 'sparian' meaning 'to refrain from' or 'to be frugal.' The two meanings (using little AND being merciful) both come from the idea of restraint.
It's fascinating that one word means both 'stingy with resources' AND 'merciful to a person'—the connection is that both require restraint, whether restraining yourself from spending or from harming someone!
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