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

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

The Osaka-based company plans to expand the drug into first-line gastric and pancreatic cancer settings, the filing showed.

From The Wall Street Journal • Oct. 22, 2025

The technique clearly shows whether a tumour is sensitive or resistant to Carboplatin, one of the standard first-line chemotherapy treatments for ovarian cancer.

From Science Daily • Dec. 6, 2024

Police also used a liquid known as Bluestar that is meant to be a first-line method of picking up blood stains not visible to the human eye.

From Los Angeles Times • Jun. 1, 2024

He was put on a standard regimen of four first-line antibiotics, similar to what WHO recommended for anyone who contracted TB.

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