pro·pri·o·cep·tor 
(prō′prē-ō-sĕptər)
(prō′prē-ō-sĕptər)n.
A sensory receptor, found chiefly in muscles, tendons, joints, and the inner ear, that detects the motion or position of the body or a limb by responding to stimuli arising within the organism.
[Latin proprius, one's own; see per1 in the Appendix of Indo-European roots + (RE)CEPTOR.]
pro′pri·o·ceptive adj.