1. The point at which something comes into existence or from which it derives or is derived.
2. Ancestry: "We cannot escape our origins, however hard we try" (James Baldwin).
3. The fact of originating; rise or derivation: The rumor had its origin in an impulsive remark.
4. Anatomy The point of attachment of a muscle that remains relatively fixed during contraction.
5. Mathematics The point of intersection of coordinate axes, as in the Cartesian coordinate system.

Synonyms: These nouns signify the point at which something originates. Origin is the point at which something comes into existence: The origins of some words are unknown.
When origin refers to people, it means parentage or ancestry: "He came . . . of mixed French and Scottish origin" (Charlotte Brontë).
Inception is the beginning, as of an action or process: The researcher was involved in the project from its inception.
Source signifies the point at which something springs into being or from which it derives or is obtained: "The mysterious . . . is the source of all true art and science" (Albert Einstein).
Root often denotes what is considered the fundamental cause of or basic reason for something: "Lack of money is the root of all evil" (George Bernard Shaw).