1

mainline

verb main·line \ ˈmān-ˌlīn \
|Updated on: 8 Jul 2018

Definition of mainline

slang : to take by or as if by injecting into a principal vein
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

in the meaning defined at transitive sense

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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

in the meaning defined above

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NEW! Time Traveler

main line

noun

Definition of main line

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

Recent Examples of main line from the Web

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

First Known Use of main line

1841

in the meaning defined at sense 1

See Words from the same year
NEW! Time Traveler

MAINLINE Defined for English Language Learners

mainline

Definition of mainline for English Language Learners

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


mainline

Definition of mainline for English Language Learners

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


main line

Definition of main line for English Language Learners

  • : an important highway or railroad line


Medical Dictionary

mainline

verb main·line \ ˈmān-ˈlīn \

medical Definition of mainline

mainlined; mainlining
slang : to take by or as if by injecting into a principal vein
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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