mainline

In real, traceable use. Part of the curated seed collection; community review is coming.

Meaning · English

To inject (a drug) directly into a vein.

Register: slang

Where it’s used: Used American English

Examples

The patient skinpopped for 1½ years and then started to mainline heroin.

Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30)

Sources & notes

Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).

Common questions

What does “mainline” mean?

To inject (a drug) directly into a vein.

Is “mainline” formal or informal?

mainline is generally slang.