verb
- injects a drug directly into a vein
Usage: slang; drug-related
noun
- principal railway lines or routes
Examples
- The freight trains use the mainlines to transport goods across the country.
- Several mainlines converge at the central station.
- The company operates trains on major mainlines throughout the region.
- Traffic was diverted from the mainlines due to construction work.
- The new high-speed rail will connect to existing mainlines.