 |
| English thesaurus | |||
| |||
| HARD | |||
|
Helmet : 84 phrases in 12 subjects |
| Astronautics | 4 |
| Aviation | 4 |
| British usage, not spelling | 1 |
| Diplomacy | 1 |
| General | 13 |
| Historical | 1 |
| Hobbies and pastimes | 4 |
| Labor law | 2 |
| Life sciences | 1 |
| Military | 46 |
| Security systems | 1 |
| Technology | 6 |