DictionaryinclusionTrapped material
noun

inclusion

Foreign material trapped inside a mineral, cell, or other substance.

The jeweler spots a tiny inclusion deep inside the diamond.

Etymology

The Latin verb means to enclose. A physical inclusion is material shut inside another substance, such as a fragment enclosed within a crystal.

More examples

  • This quartz crystal contains several fluid inclusions.
  • A brittle inclusion weakens the steel.
  • Under the microscope, the cell shows a dark inclusion.

Forms

inclusion · inclusions

Similar words

impurity
Unwanted material present, not necessarily a distinct trapped particle.
contaminant
An introduced substance that makes material less pure or safe.