picometer
/ˈpaɪkəˌmitər/
noun
- A unit of length equal to one trillionth of a meter (10⁻¹² meters), used in science to measure atoms and molecules.
- Scientists measure the distance between atoms in picometers.
- The diameter of a hydrogen atom is about 53 picometers.
- A picometer is so small that it takes a million of them to make a nanometer.