: being the preferred, standard, or first choice
first-line treatment of tuberculosis
compare second-line

Word History

First Known Use

1919, in the meaning defined above

Time Traveler
The first known use of first-line was in 1919

Dictionary Entries Near first-line

Cite this Entry

“First-line.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/first-line. Accessed 9 Dec. 2022.

Medical Definition

first-line

adjective
: being the preferred, standard, or first choice
first-line treatment of advanced breast cancer
compare second-line
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