| Webster's Online Dictionary |
| Expressions | Domain | Definition | |
| Hallinger shield | Mining | A tunneling shield of Hungarian design, successfully employed for tunneling at Dortmund and under the Danube. It is valuable for working in very soft ground. It incorporates a mechanical excavator and does not entail the use of timbering to protect the miners. (references) | |
Source: compiled by the editor from various references; see credits. | Top | ||
