1. a word or expression that is being defined
Usage: logic; philosophy

Examples

• In the definition ‘A triangle is a three-sided polygon,’ the word ‘triangle’ is the definiendum.
• The definiendum appears on the left side of the equation in formal definitions.
• Students must clearly identify the definiendum before attempting to provide a definition.
• In logic textbooks, the definiendum is typically distinguished from the definiens.
• The professor asked us to underline the definiendum in each dictionary entry.