first-line

adjective

ˈfərst-ˈlīn How to pronounce first-line (audio)
Synonyms of first-linenext
: being the preferred, standard, or first choice
first-line treatment of tuberculosis
compare second-line

Synonyms of first-line

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Examples of first-line in a Sentence

surgery is usually not considered a first-line treatment for this type of cancer
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Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The study, which was presented at a major cancer meeting called the European Society for Medical Oncology Congress, did not test whether the combination was better than other first-line treatment approaches. — Annika Kim Constantino, CNBC, 24 Oct. 2026 Pelvic floor therapy becomes a first-line referral, not a last resort. — Hanna Wickes, Charlotte Observer, 19 Oct. 2026 The results suggest that the RTX Spark's gaming ambitions, while no slouch, are a welcome extra rather than a first-line reason to buy one of these machines. — Joe Osborne, PC Magazine, 17 Oct. 2026 Vaginal estrogen is a first-line treatment to prevent more UTIs. — Helen Carefoot, Flow Space, 14 Oct. 2026 See All Example Sentences for first-line

Word History

First Known Use

1919, in the meaning defined above

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

Rhymes for first-line

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Browse Nearby Words

first light
first-line
firstling
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Cite this Entry

“First-line.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/first-line. Accessed 1 Nov. 2026.

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Medical Definition

first-line

adjective
ˈfərst-ˈlīn How to pronounce first-line (audio)
: being the preferred, standard, or first choice
first-line treatment of advanced breast cancer
compare second-line
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