plural of mast cell

A resident cell of connective tissue that contains many granules rich in histamine and heparin.

(physics, chemistry) A conservation law of classical physics that states that the total mass of a closed system remains constant regardless of the chemical or physical changes that take place within it.

A large four-masted sailboat.

Method of transport, usually public, that carries people in greater quantities than a typical private method such as car.

(informal, biology) The pituitary gland.

plural of mass noun

plural of mass murder

The killing of a large number of people over a short period of time.

Someone who commits a mass murder.