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

I was told that there were a variety of first-line drug treatment options available on the NHS, including Doxylamine Succinate and Pyridoxine Hydrochloride, a drug which goes by the brand name Xonvea in the UK.

From BBC ● Jun. 29, 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

For over 60 years, metformin has been a first-line treatment for type 2 diabetes, yet scientists have not fully understood how it works.

From Science Daily ● Mar. 25, 2026

A culture showed that the bacilli from his body were resistant to all four of the drugs he’d been given, and to one other first-line antibiotic as well.

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