A plurimeter is a hand-held measuring instrument for determining surface area or relative angles between surfaces. The device uses mechanical action for calculating the result, analogous to a slide rule. In modern technology, these results are computed by calculator or computer rather than by mechanical instrument.
References Croft PR, Nahit ES, Macfarlane GJ, Silman AJ (May 1996). "Interobserver reliability in measuring flexion, internal rotation, and external rotation of the hip using a plurimeter". Ann. Rheum. Dis. 55 (5): 320–3. doi:10.1136/ard.55.5.320. PMC 1010170. PMID 8660107.