Mass can refer to:

• Mass, a physical quantity describing the amount of matter in an object
• Mass (liturgy), the primary worship service of many Christian churches
• Mass (music), a choral composition that sets liturgical text to music.
• Mass (medicine), a tumor
• Mass (theatre), a 1971 musical play by Leonard Bernstein based on Roman Catholic liturgy
• Mass (band), a post-punk band who recorded for the 4AD label
• Mass., an abbreviation for the U.S. state of Massachusetts
• Landmass (also land mass)
• "Mass", an alias of electronic musician Peter Harris
• Body mass index, a health indicator related to human body weight and height
• Thermal mass, a mass which absorbs heat
• Muscle mass, a bodybuilding term concerning the amount of muscle in a person's body
• hoi polloi (or "the masses"), a term that usually refers to common people

In the plural form, the masses, the term may refer to:

• The working class or the people ("the masses"). See also multitudes. Masses are disorganized, as opposed to classes (see class consciousness).
• Hoi polloi (or "the masses"), a term that usually refers to common people
• The Masses, a Socialist magazine

An adjective indicating a large quantity, as in:

• mass production
• mass transit
• mass communication
• mass education
• mass market
• mass media
• mass murder
• mass suicide
• weapons of mass destruction
• mass burial
• mass hysteria
• mass storage

Masse | Messe | Masse | Massa | Masa