1) Measuring instrument 
A penetrometer is a device to test the strength of a material. ==Soil== There are many types of penetrometer designed to be used on soil. They are usually round or cone shaped. The penetrometer is dropped on the test subject or pressed against it and the depth of the resulting hole is measured. The measurements find whether the soil is strong enou...
instrument for measuring firmness or consistency of substances
An obsolete instrument for measuring the penetrating power of X-rays from any given source. ... Origin: penetration + G. Metron, measure ... (05 Mar 2000) ... 
(pen″ә-trom´ә-tәr) an instrument for measuring the penetrating power of x-rays; qualimeter.
Type: Term Pronunciation: pen′ĕ-trom′ĕ-tĕr Definitions: 1. An obsolete instrument for measuring the penetrating power of x-rays from any given source.
A device used for measuring the hardness or softness of the track by measuring the extent to which the device penetrates the ground.