A person or device that causes asphyxia; something that suffocates or deprives of oxygen.
From 'asphyxiate' plus the agent suffix '-or,' forming a noun that means something or someone that causes the action.
You'll rarely hear 'asphyxiator' in everyday speech because it sounds clinical and unsettling—it's the kind of word that appears in forensic reports and medical textbooks rather than casual conversation.
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