first-line

[ furst-lahyn ]

/ ˈfɜrstˈlaɪn /

available for immediate service, especially combat service: first-line troops.

of prime importance or quality.

Origin of first-line

First recorded in 1895–1900

Eagerly, expectantly, the boys gathered in the first-line trenches to watch the fun.

Prairie Gold |Various
Further north the enemy's first-line system for a distance of about half a mile beyond Beaumont Hamel was also in our hands.

World's War Events, Vol. II |Various
In the first-line trenches they could see no one and felt uncertain what to do.

The Birth of Yugoslavia, Volume 1 |Henry Baerlein
This was only the first-line strength of the Germans, the reserves being massed in the rear.

America's War for Humanity |Thomas Herbert Russell

Under pressure of this success the Russians abandoned their first-line positions in the Meste-Canaste sector.

The Story of the Great War, Volume VI (of VIII) |Various

first-line

acting or used as a first resort first-line treatment; first-line batsmen