noun
crystal
KRIS-tul/ˈkrɪstl/
A solid whose atoms are arranged in a regular repeating pattern.
Each clear quartz crystal has regular, flat faces and a pointed tip.
Etymology
Greek krystallos named both ice and crystal: the ancients regarded the mineral as petrified ice. The mineral name later acquired the scientific sense defined by regular internal structure.
In context
an obsidian is actually natural volcanic glass so it's not a mineral because it does not have a crystal structure
More examples
- Sugar crystals grow as water evaporates from the solution.
- The quartz crystal has flat faces and sharp edges.
- Scientists grow crystals in the lab to study their structure.
Forms
crystal · crystals
crystalline adjective — Having atoms arranged in a repeating pattern.
crystallize verb — To form crystals or cause crystals to form.
Similar words
- crystallite
- A very small crystal, often within a larger solid.