The Weight stat indicates a character's overall heaviness. It has appeared in Fire Emblem: Path of Radiance and Fire Emblem: Radiant Dawn. It is meant to distinguish the character's own physical weight from the additional weight from their armor and/or their mount.
Characters are able to rescue other units if their weight is higher by two as well as shove them in Path of Radiance, although this was later changed in Radiant Dawn to the Constitution stat being required instead to be no more than two below another unit's weight in order for them to perform a shove. Mounted characters and the Laguz are usually exceptionally heavy which allows for them to be able to rescue others easily.
Unlike other stats, it cannot increase with Level Ups as it lacks a growth rate, though it may be affected by Class Change. Laguz in their transformed state usually gain large amounts of weight due to their increased body mass. Statue Frags can cause a character's weight to increase along with their Constitution.