/ ˈmeɪnlaɪn; NAmE / adjective , verb
■ adjective
( especially NAmE ) belonging to the system, or connected with the ideas that most people accept or believe in
SYN mainstream :
mainline churches / faiths
■ verb
( slang ) to take an illegal drug by injecting it into a vein :
[ vn ]
At 18 he was mainlining heroin.
[also v ]