Superlative form of feeble: most feeble.(adjective)
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Use "feeblest" in a sentence
"Q.E.D. Puns are the feeblest species of humor because they are ephemeral: whatever comic force they possess never outlasts the split second it takes to resolve the semantic confusion."
"Abdi showed the auctioneer his depressing basement studio, and de Pury delivered the least convincing, feeblest "terrific" of the entire season."
"Here's the feeblest pillar of Europe's freedom temple cracking yet again."