 |
| travelling wave: 45 phrases in 14 subjects |
| Antennas and waveguides | 2 |
| Biology | 2 |
| British usage, not spelling | 2 |
| Communications | 2 |
| Electronics | 12 |
| General | 1 |
| High energy physics | 4 |
| Measuring instruments | 2 |
| Mining | 1 |
| Natural resourses and wildlife conservation | 2 |
| Optics branch of physics | 2 |
| Physics | 10 |
| Radio | 1 |
| Technology | 2 |