origin

1. The less movable of the two points of attachment of a muscle, that which is attached to the more fixed part of the skeleton. 2. The starting point of a cranial or spinal nerve. The former have two origins: the ental o., deep o., or real o., the cell group in the brain or medulla, whence the fibers of the nerve begin, and the ectal o., superficial o., or apparent o., the point where the nerve emerges from the brain. [L. origo, source, beginning, fr. orior, to rise]

- o. of replication a sequence of the bacterial genome required for the initiating of a replicating fork by leading strand synthesis.

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or·i·gin 'ȯr-ə-jən, 'är- n

1) the point at which something begins or rises or from which it derives

2) the more fixed, central, or larger attachment of a muscle compare INSERTION (1)

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n. (in anatomy)

1. the point of attachment of a muscle that remains relatively fixed during contraction of the muscle. Compare insertion.

2. the point at which a nerve or blood vessel branches from a main nerve or blood vessel.

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or·i·gin (orґĭ-jin) [L. origo beginning] the source or beginning of anything, especially the more proximal, fixed end or attachment of a muscle (as distinguished from its insertion), or the site of emergence of a peripheral nerve from the central nervous system.