1. a breathing hole or opening in insects, spiders, and some other arthropods
Usage: biology
2. a blowhole on the top of a whale’s or dolphin’s head
Usage: marine biology
3. a small opening or vent, especially one that allows air or gas to pass through

Examples

• The insect breathes through tiny spiracles along its body.
• Grasshoppers have spiracles on their abdomen for gas exchange.
• The whale’s spiracle closed tightly as it dove underwater.
• Dolphins surface regularly to breathe through their spiracles.
• The scientist examined the spiracles under a microscope.
• Each spiracle is connected to the insect’s respiratory system.
• The volcanic rock contained small spiracles where gas had escaped.