Gill may refer to one of the following.

• Gills are a respiratory organ in aquatic organisms.
• Gills are the spore-bearing structure in agarics (gilled mushrooms).
• A gill (pronounced ) is also a unit of measurement in the U.S. customary and Imperial systems.
• Gill is the nickname of an Israeli fourth-generation ATGM (anti tank guided missile). The Gill is one of the model of the IDF "Spike" family.
• Gill crater on the Moon.
• Gill is also a boss character from the popular Street Fighter III series of Video Games.