Wiktionary
alt. 1 A mechanical device that measures the ease of penetration of an object into a semisolid. 2 A device that measures the penetrating power of electromagnetic radiation (especially X-rays). n. 1 A mechanical device that measures the ease of penetration of an object into a semisolid. 2 A device that measures the penetrating power of electromagnetic radiation (especially X-rays).
Wikipedia
A penetrometer is a device to test the strength of a material.
Usage examples of "penetrometer".
In the huge remaining expanse the penetrometers served as remote sensing stations for regions not yet entered by explorers on the ground.
As pure fluorine was about the most vicious substance known to man, it was high on the list of prohibited materials - but, like the rockets which drove the penetrometers down to their targets, it was essential for the mission.