Superlative form of smelly: most smelly.(adjective)
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Use "smelliest" in a sentence
"That night, I lay in bed, staring into the gray darkness at the bunk above me, now occupied by the smelliest kid I knew."
"The zorrilla Ictonyx striatus, or Striped Polecat, is considered the smelliest animal on earth."
"In a poll, 76% of Americans say that trash is the smelliest thing in the house, ranking ahead of pets, shoes, husbands and kids, according to a 2010 survey done by Glad, a unit of Clorox Co. Baby diapers are the worst offenders, followed by spoiled refrigerator food."