Superlative form of damp: most damp. Most damp.(adjective)
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Use "dampest" in a sentence
"Machine # 8 once had the saddest, dampest love letter, still in its envelope."
"The neon maniacs emphasis on the “maniacs,” as I saw no “neon” in this film, who melt if exposed to water, live in one of the dampest, foggiest places in California – San Francisco!"
"I planted some here, in our dampest soil, and it died within days."