A HICCUP IS A SPASM OF YOUR DIAPHRAGM.

The diaphragm is the dome-shaped muscle that separates the chest from the abdomen and works in conjunction with the lungs to help us breathe. When you take a breath in, the diaphragm contracts, flattening and pulling downward as it does so in order to make more room in the chest cavity for the influx of oxygen. When there’s a disturbance in the nerve passageways leading from the brain to the diaphragm—which can happen by swallowing too much air, eating too quickly, or experiencing anxiety—the diaphragm spasms. You experience these spasms as hiccups.
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