- Any of numerous arachnids of the order Araneae, having a body divided into a cephalothorax bearing eight legs, two poison fangs, and two feelers and an unsegmented abdomen bearing several spinnerets that produce the silk used to make nests, cocoons, or webs for trapping insects.
- In audio, the assembly which holds the voice coil of a dynamic loudspeaker centered in the magnetic gap. The spider is usually a corrugated circular piece of specially coated fabric. The name comes from the early days of loudspeakers when it was made of a plastic material that resembled the legs of an arachnid.
