The courage, initiative, and resourcefulness to do something that needs to be done without being asked.
Origins are uncertain but likely from Scottish English, possibly related to dialectal words meaning 'to take by the throat.' The word gained popularity in American English in the 19th century as a way to describe practical determination and common sense.
Gumption is a uniquely American success word—it became a favorite of self-made industrialists and entrepreneurs who wanted to celebrate getting things done. You'll notice it's rarely used in formal writing today, which is why hearing it sounds refreshingly old-fashioned and earnest.
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