A person who is limited to small, limited, petty or unimportant scale of things.(noun)
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Use "small-timer" in a sentence
"There the Darknight Detective stops another small-timer (hired by Adam Strange) from stealing an ancient stone tablet."
"Maggio's story and plotting can be predictable, but he gets a real feel for the life of a small-timer, not just from Farina but from the others who populate Joe's strata of Chicago life."
"A small-timer up to now, the money-hungry Clay may be in over his head, and unfortunately, his crew begins to sense it."