Plural of constrictor; things that constrict, especially snakes that kill by constriction, or muscles that narrow or tighten.
From constrict plus the agent noun suffix -or/-er. Constrictors can be animals (like boa constrictors) or muscles (like pharyngeal constrictors in your throat).
Your throat has three pharyngeal constrictors that work together to swallow and push food down—if you ever choke, these muscles might be working against you instead of for you.
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