10 Must-Know Metrology Terms

Metrology terms can be a bit intimidating, especially considering that anytime you mention Metrology in a casual setting, you inevitably get asked about the weather—“did you mean meteorology?”

Metrology is the study of measurement, and at Made to Measure, we’ve performed dimensional inspection and quality control services for the better part of 40 years. And just like every industry, we have our own jargon that needs decoding.

To help, we’re taking it down to the very basics with these 10 must-know metrology terms with our team at Made to Measure!


The process of officially qualifying a metrology lab to perform inspections. Accreditation is done by an unbiased 3rd-party organization to verify that the lab meets certain standards. A great example of an accreditation is the ISO 17025:2017 standard.


AUKOM is a globally-recognized CMM metrology training program with the international goal of reducing uncertainty and conflict in measurement. All AUKOM CMM training courses are vendor-neutral, allowing you to take the skills that you learn and apply them to any coordinate measuring machine or CMM programming software. Made To Measure is proud to be one of only four certified providers of AUKOM training in the US.


Calibration is a process that reduces uncertainty by comparing two measurements–one being a standard of known accuracy or value, and one of an unknown accuracy or value. The difference between these two values is then used to achieve an accurate result.

Photo Courtesy of Jeff Schuler


While there are certainly complicated metrology terms, some are a bit easier to grasp. Dependability is the degree to which a machine or tool is operable and capable of performing its required function at any point in its operating time.


In numerical data sets, deviation is the difference or distance of an individual observation or data value from the center point (often the mean) of the set distribution. Essentially, deviation is how different a value is compared to the mean.


Commonly referred to as a bar graph, a histogram is a visual representation of numerical data.


Perhaps the most important of all metrology terms is metrology itself! The Science of Measurement; embracing both experimental and theoretical determinations at any level of uncertainty. While metrology is an extremely general area of study, there are multiple fields within. Legal metrology, applied metrology, and scientific metrology are all individual fields in and of themselves.


While dependability is similar to repeatability (and related to it!), they are not the same. Variation between measurements obtained when one measurement device is used several times by the same person to measure the same characteristic on the same product. Put simply, it is the degree to which a measurement tool can do its job repeatedly without losing accuracy.


In metrology terms, tolerance is the minimum and maximum amount a product is allowed deviate from its ideal form while legally meeting customer requirements.


The act of confirming that a product or service meets the requirements for which it was intended.

Get Your Questions Answered at Made to Measure

Are you wondering how metrology can help your quality control and production processes? Now that you’ve read up on metrology terms with our experts, don’t hesitate to contact us online. We’re ready to help you with our full suite of metrology services, CMM equipment, and metrology training courses. When you need a quality control lab that’s dependable and repeatable as a CMM, trust Made to Measure!