| Answer | Crossword Clue |
|---|---|
| etalons | ETALON, a device used to measure wave length |
| etalon | a device used to measure wave length |
| dosimeter | A device used to measure an absorbed dose of ionizing radiation |
| dosimeters | A device used to measure an absorbed dose of ionizing radiation |
| impellors | A similar device turned by the flow of water past a ship's hull, used to measure speed or distance traveled |
| impellers | A similar device turned by the flow of water past a ship's hull, used to measure speed or distance traveled |
