extrinsic

adj

1. External; separable from the thing itself; inessential.
2. Not belonging to something; outside.

   “1 Experimental set up for strength testing of the flexor hallucis muscle of the right foot To ensure accurate positioning of the hallux onto the load cell, and to minimise the influence of the extrinsic muscles of the foot (ankle plantarflexors and flexor hallucis longus) and the 2nd to 4th toes, a purpose-built wooden platform was constructed and positioned under the NWBB.”

noun

1. An external factor.