1

mainline

play
verb main·line \ ˈmān-ˌlīn \

Definition of mainline

transitive verb
slang :to take by or as if by injecting into a principal vein
intransitive verb
slang :to mainline a narcotic drug

Examples of mainline in a Sentence

  1. His addiction grew worse when he began mainlining.

Recent Examples of mainline from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mainline.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of mainline

1938


2

mainline

adjective

Definition of mainline

:being part of an established group; also :being in the mainstream

Recent Examples of mainline from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mainline.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of mainline

1941


main line

noun

Definition of main line

1 :a principal highway or railroad line
2 slang :a principal vein of the circulatory system

First Known Use of main line

1841


MAINLINE Defined for English Language Learners

mainline

play
verb

Definition of mainline for English Language Learners

  • : to inject (a drug) directly into a vein


mainline

adjective

Definition of mainline for English Language Learners

  • : belonging to an established and widely accepted group or system


main line

noun

Definition of main line for English Language Learners

  • : an important highway or railroad line


Medical Dictionary

mainline

play
verb main·line \ ˈmān-ˈlīn \

medical Definition of mainline

mainlined; mainlining
transitive verb
slang :to take by or as if by injecting into a principal vein
intransitive verb
slang :to mainline a narcotic drug (as heroin)

main line

noun

medical Definition of main line

slang
:a principal vein of the circulatory system

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