Spider is a c/5 orthogonal spaceship that was discovered by David Bell on April 14, 1997. It is the smallest known c/5 orthogonal spaceship. Its side sparks have proven to be very useful in constructing puffers and rakes.

On March 7, 2019, Martin Grant found a 601-glider synthesis of spider, making it the first c/5 orthogonal spaceship to be synthesized. Optimizations have since been found to reduce the glider count. A spider gun was constructed by Entity Valkyrie on January 26, 2020, and a glider-to-spider converter was constructed by Goldtiger997 on March 12.

The spider synthesis ranked second place in the Pattern of the Year 2019 competition on the ConwayLife.com forums, behind David Hilbert.