'mainline' definitions:
Definition of 'mainline'
From: WordNet
verb
Inject into the vein; "She is mainlining heroin"
Definition of 'mainline'
From: GCIDE
- mainline \main"line`\ (m[=a]n"l[imac]n`) v. t.
- 1. to inject (illegal drugs) into the vein; as, he preferred to mainline heroin rather than sniff coke. [WordNet 1.5]