Superlative form of thrifty: most thrifty.(adjective)
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Use "thriftiest" in a sentence
"Kelley criticizes scholars who, in attempting to counter racist stereotypes, “are often too quick to invert them, remaking the black proletariat into the hardest-working, thriftiest, most efficient labor force around.”"
"Instead textbooks show African Americans of the era as the hardest-working, thriftiest, most sober, and family oriented of all Americans."
"The thriftiest savers, cautious souls who had shunned the stock market as reckless speculation, saw their carefully tended nest eggs vanish overnight as banks collapsed."