A leavening agent.

(sports) A professional athlete who is free to play for or sign a contract to play for any team. / A person who acts freely, or without constraint to a higher power.

(Britain) A person or company that acts in the sale, lease or maintenance of land, property, real estate etc for another. / (archaic) A land bailiff.

Any food additive added to produce a shiny protective coating

Any substance added to a product in order to whiten it; a bleach

Any substance that will produce a foam under specified conditions

any substance used to increase viscosity, especially of a food product

A member of an intelligence agency whose identity or affiliation is kept confidential.

Any compound that has an affinity for water such that it will extract it from other materials; a desiccant

A spy who pretends to be a double agent for one side, while actually acting as a double agent for the other side.