- gasMatter in an intermediate state between liquid and plasma that can be contained only if it is fully surrounded by a solid (or in a bubble of liquid, or held together by gravitational pull); it can condense into a liquid, or can (rarely) become a solid directly by deposition.
- chaosThe unordered state of matter in classical accounts of cosmogony.
- chao-Chaos.
- chaotropismThe ability to disrupt hydrogen bonding, especially within or between biological molecules