| A | B |
| amorphous | without a defined shape; fibers composed of a loose arrangement of polymers that are soft, elastic, and absorbing (for example, cotton) |
| crystalline | regularly shaped; fibers composed of polymers packed side by side, which make it stiff and strong (for example, flax) |
| direct transfer | the passing of evidence, such as fiber, from victim to suspect or vice versa |
| fiber | the smallest indivisible unit of a textile, it must be at least 100 times longer than wide |
| mineral fiber | a collection of mineral crystalls formed into a recognizable pattern |
| monomer | a small molecule that may bond to other monomers to become a polymer |
| natural fiber | a fiber produced naturally and harvested from animal, plant, or mineral sources |
| polymer | a substance composed of long chains of repeating units |
| synthetic fiber | a fiber made from a man-made substance such as plastic |
| secondary transfer | the transfer of evidence such as a fiber from a source (for example, carpet) to a person (suspect), and then to another person (victim) |
| textile | a flexible, flat material made by interlacing yarns (or treads) |
| yarn | fibers that have been spun together |