Definitions

1. noun

the main or primary route or supply of something, especially a railway or a source of information or energy.

“The mainline of the railroad was severely damaged in the storm.”

2. verb

to supply or provide something, especially a railway or a source of information or energy.

“The company mainlined the new pipeline to meet the increasing demand.”

3. verb

to inject or administer a substance, especially a drug, directly into a person’s bloodstream.

“The doctor mainlined the patient with a powerful painkiller.”