Inelastic describes something that doesn't stretch, bend, or change easily. A steel rod is inelastic because you can't pull it longer like a rubber band. Old, dried-out elastic in worn sweatpants becomes inelastic and won't snap back into shape anymore.

In economics, the word describes how much people's buying habits change when prices go up or down. Inelastic demand means people keep buying roughly the same amount even when prices change. Gasoline has fairly inelastic demand: when gas prices rise, most people still need to drive to work and school, so they keep buying gas even though it costs more. Medicine is another example: if you need insulin or heart medication, you'll buy it whether it costs $50 or $100 because your health depends on it.

Compare this to elastic demand, where people quickly change how much they buy when prices shift. If movie tickets double in price, many families might wait to stream movies at home instead. The demand for movie tickets is more elastic because people can easily choose alternatives.

The word also appears in physics to describe materials that don't return to their original shape after being stretched or compressed. When you crumple a piece of paper, it stays crumpled because paper is inelastic. Understanding whether something is elastic or inelastic helps explain how materials behave and how markets work.