That's a great question. The answer is yes.
If you have a wrist-watch, it probably has an "LCD" , which stands for "liquid crystal display". Since a crystal is a solid, the name already should be a hint that there's something not quite solid or liquid. There are other forms of matter that don't fall into the three standard categories, but liquid crystals are probably the most familiar.
If you look at the arrangement of molecules in a liquid cystal, along some directions you will find a regular, ordered array, just like in any solid crystal. In other directions, youíll find an irregular, fluctuating pattern, just like in any liquid. For example, in one type of liquid crystal the molecules form into an evenly spaced pattern of layers, but donít have any regular pattern within the layers.
Your question gives me an excuse to air a pet peeve. Often in school we are given lists to memorize: the three states of matter, the five types of magnet, the three types of government, etc. Those may provide convenient names for some purposes, but they really donít accurately describe the way the world actually is.
(republished on 07/25/06)