• In philosophy, substance means, approximately, that element of an object without which it would not exist. In the millennia-old Aristotelian tradition, as well as early modern traditions that follow it, substances are treated as having attributes and modes . For in-depth articles on the topic, see objecthood and substance theory. For Baruch Spinoza, substance meant also the inner essence or what "stands under" (from the Latin root).

• For the chemical concept, see chemical substance.
• Substance is sometimes used as a euphemism for harmful drugs.

• Substance, a 1988 album of Joy Division songs recorded in 1977–1980
• Substance, a 1987 album by New Order.