Wiktionary
n. 1 A device for evaluating various tensile properties of a material, such as Young's modulus, ultimate tensile strength and Poisson's ratio. 2 (alternative spelling of tensiometer English)
Wikipedia
A tensometer is a device used to evaluate the tensile properties of materials such as their Young's modulus (i.e. the degree to which they stretch under stress) and tensile strength. It is usually a universal testing machine loaded with a sample between two grips that are either adjusted manually or automatically to apply force to the specimen. The machine works either by driving a screw or by hydraulic ram. The latter have the great advantage of being able to create much more complex loading patterns, such as the cyclical loads needed for measurement of fatigue strength. Machines can also be equipped with environmental chambers for testing at different temperatures or variable humidity, for example.