| Term | Definition |
| ocular lens | eyepiece (magnifies 10x) |
| objective lenses | lenses of different powers (4x, 10x, and 40x) |
| body tube | maintains the correct distance between the ocular lens and the objectives |
| coarse-adjustment knob | moves the stage up and down to allow for focusing |
| fine-adjustment knob | moves the stage very slightly to bring the image into sharper focus |
| stage | supports a slide |
| stage clips | hold the slide in place for viewing |
| diaphragm | controls the amount of light coming through the stage |
| light source | provides light for viewing |
| arm | supports the body tube |
| base | supports the microscope |
| nosepiece | holds the objective lenses |