A needle is a thin, pointed tool used for sewing, made of metal with a tiny hole (called an eye) at one end for threading. You push the needle through fabric, pulling thread behind it to join pieces of cloth together or create decorative stitches. Sewing needles come in different sizes: thick ones for heavy fabrics like denim, delicate ones for silk or embroidery.

The word also describes other thin, pointed objects. Pine trees have needles instead of flat leaves: those sharp, narrow green spikes that stay on the tree year-round. Doctors use hollow medical needles to give injections or draw blood. A compass needle is the magnetized pointer that swings toward north. Record players use a small needle (or stylus) that rides in the grooves of vinyl records to play music.

When someone says they're looking for “a needle in a haystack,” they mean searching for something tiny in a huge pile of similar-looking stuff, making it nearly impossible to find. That phrase captures how small and easily lost a needle can be.

To needle someone means to tease or annoy them with small, persistent comments, like poking them over and over (but with words instead of an actual needle).