first-line

American  

[furst-lahyn] / ˈfɜrstˈlaɪn /

adjective

1. available for immediate service, especially combat service.

   first-line troops.

2. of prime importance or quality.

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first-line British  

adjective

1. acting or used as a first resort

   first-line treatment

   first-line batsmen

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Etymology

Origin of first-line

First recorded in 1895–1900

Example Sentences

See Examples For:

first-line

Early-stage data for GSK’s drug candidate IDRx-42 presented at the American Society of Clinical Oncology’s annual meeting showed potential as a first-line treatment for gastrointestinal cancer, Jefferies says.

From The Wall Street Journal ● Jun. 2, 2026

Researchers noted that these reductions are similar to results seen with some first-line blood pressure medications.

From Science Daily ● May 10, 2026

Each time, the first-line representative said no, suggesting something like, “If you can’t afford to pay it now, set up a payment plan or apply for financial assistance.”

From Slate ● Apr. 25, 2026

Nektar stock jumped 26% after positive trial results, with analysts raising price targets and expecting first-line treatment potential.

From Barron's ● Apr. 20, 2026

Their prison hospital X-ray machines were in a decrepit state, and there was a chronic shortage of even first-line antibiotics.

From "Mountains Beyond Mountains" by Tracy Kidder and Michael French