| Answer | Crossword Clue |
|---|---|
| bronchia | BRONCHIUM, a small branch of the windpipe |
| bronchium | a small branch of the windpipe |
| nervule | small branch of a nerve in the wing of an insect |
| nervules | small branch of a nerve in the wing of an insect |
| petrology | The branch of science concerned with the origin, small-scale structure, and composition of rocks |
