Agent noun of block; something that blocks something specific.(noun)
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Use "blocker" in a sentence
"Scent blocker is not needed when squirrel hunting; what you do need is a way to slip through the woods as quietly as possible, the best advice I can give you is walk slowly and watch your step."
"Also, the pop-up blocker is not effective. camron9989"
"Investments held offshore in what is known as a "blocker corporation" can allow U.S. taxpayers to pay less tax than if the same investment were made through an onshore entity, Mr. Gordon says."