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

About half of patients with metastatic melanoma will get worse on first-line immunotherapies within a year, at which point they have scant options.

From The Wall Street Journal ● Jul. 28, 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

Some experts believe it is a debilitating reaction to steroid creams - the first-line treatment for many of the eight million people who have eczema in the UK.

From BBC ● Mar. 28, 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