The act or practice of giving or yielding something as profit or gain, or possibly an archaic term related to conceding advantage.
From 'gain' plus 'giving' (the act of yielding or presenting), likely from Middle English. This appears to be a rare compound that did not persist widely in modern English.
The word 'gaingiving' almost sounds like it could describe voluntary charity or sharing wealth, but it's so archaic that its exact historical meaning has been mostly lost—language archaeology at its finest.
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