time crystal

Etymology 1
Coined by American biologist in 2001. An analogue to crystals, which have repetitive patterns in space.

Noun

 * 1)  A periodic biological system.

Etymology 2
Coined by American physicist in 2012. An extension of the concept of a crystal to encompass time.

Noun

 * 1)  A crystal that has a structure that repeats not only in space, but also in time.