The prefix hyper- means extremely, excessively, or beyond normal. When you add it to the beginning of a word, it intensifies the meaning, like turning up the volume dial.

A hyperactive child has way more energy than usual, bouncing around when others sit still. Someone who's hypersensitive reacts more strongly to things than most people do: a hypersensitive person might feel deeply hurt by a mild criticism that wouldn't bother someone else. If you're hyperaware of the clock during a boring class, you're painfully conscious of every single minute ticking by.

In everyday speech, people sometimes use hyper by itself to describe someone who's unusually energetic or excited: “My little brother gets really hyper after eating birthday cake.”

Notice that hyper- usually suggests too much of something. A hypercritical teacher doesn't just offer helpful feedback but picks apart every tiny detail. Being hyper about something often means you've gone past the sweet spot into excess. When you see hyper- at the start of a word, expect whatever follows to be cranked up past the normal range.