first-line
adjective
: being the preferred, standard, or first choice
first-line treatment of tuberculosis
compare second-line
Examples of first-line in a Sentence
surgery is usually not considered a first-line treatment for this type of cancer
Recent Examples on the Web
Star first-line forwards Leo Carlsson and Cutter Gauthier top an important list.
—
Eric Stephens, New York Times, 6 Mar. 2026
The American College of Physicians recommends CBT-I as the first-line treatment for chronic insomnia.
—Allison Palmer
march 4, Charlotte Observer, 4 Mar. 2026
Now, in a new paper in the journal Cell Press Blue, researchers report that if the tissue’s first-line defenses fail, then what could have been a mild infection spirals out of control.
—Veronique Greenwood, Time, 27 Feb. 2026
Metformin is the first-line medication for the treatment of type 2 diabetes.
—Tom Gavin, EverydayHealth.com, 27 Feb. 2026
See All Example Sentences for first-line
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Eric Stephens, New York Times, 6 Mar. 2026
The American College of Physicians recommends CBT-I as the first-line treatment for chronic insomnia.
—Allison Palmer
march 4, Charlotte Observer, 4 Mar. 2026
Now, in a new paper in the journal Cell Press Blue, researchers report that if the tissue’s first-line defenses fail, then what could have been a mild infection spirals out of control.
—Veronique Greenwood, Time, 27 Feb. 2026
Metformin is the first-line medication for the treatment of type 2 diabetes.
—Tom Gavin, EverydayHealth.com, 27 Feb. 2026
See All Example Sentences for first-line
Cite this Entry
“First-line.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/first-line. Accessed 13 Mar. 2026.
Copy CitationMedical 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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