Squiggly describes a line that twists and curls in an irregular way — not straight, not a neat circle, just wandering. Think of the line a child draws when they scribble, or the wavy underline your computer puts under a word it thinks is spelled wrong, or the shape of a worm moving. The key idea is that the curves are messy and unplanned. If a curve is smooth and regular, like the edge of a plate, we would not call it squiggly. It is a friendly, informal, slightly childish-sounding word — you hear it from teachers, parents, and designers, and you see it in everyday writing, but you would not usually put it in a serious report. People also use it about handwriting that is hard to read: "his signature is just a squiggly mess." A little more loosely, people say a person's stomach feels squiggly when they are nervous, though that use is rarer. The noun it comes from, a squiggle, is the mark itself; squiggly is what that mark looks like.

彎彎曲曲的、歪歪扭扭的（形容線條）