Superlative form of poor: most poor. most poor.(adjective)
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Use "poorest" in a sentence
"With fanfare and flags waving, leaders thanked Venezuelan President Hugo Chavez for promising eight million gallons of the oil to low-income families in Serrano's New York district, which he describes as the poorest in the nation."
"The gap between the richest and poorest is wider than ever, with the top earning 20% receiving more than 49% of the income generated last year."
"But to make a big deal of Egypt going from 47th to 48th poorest is really trying to make the data say something that the data is not good enough to support."