Glossary 

Mass Measurement - Vocabulary & Definitions

• Attribute - A property of an object or person. 

• Direct (measurement) - A property that can be easily measured directly such as the weight of an object on some scales, or when two objects can be compared directly, e.g. to compare the mass of two bags, a person can pick them both up and feel which is heavier. This process is called hefting. 

• Gram (g) - A metric measure of mass (which we feel as weight).

• Heft - To test the weight of something by holding it in your hand. 

• Indirect (measurement) - A property that cannot be easily measured directly on scales, or by hefting the objects to compare them, such as the mass of an elephant or a house.

• Kilogram (kg) - The international standard (SI) unit of mass (which we feel as weight). There are 1,000 grams in a kilogram.

• Mass - A measure of how much matter is in an object . Although slightly different mass and weight are generally interchangeable.

• Metric  - A system of measuring based on the metre for length, the kilogram for mass and the second for time.

• Scales - An instrument used to measure weight .

• Weight - How heavy something is when affected by gravity. Although slightly different mass and weight are generally interchangeable.