adjective / noun

main

MAYN/meɪn/

Serving as the principal part of a larger whole.

The building's main entrance has broad double doors beneath a portico.

A building’s unmistakable main entrance: broad central double doors beneath a projecting portico, approached by wide steps and a broad walkway, contrasted with a small, plain side entrance.

Etymology

Mægen supplied the idea of power or strength in compounds. Main first described something notably large or strong, then shifted from size and strength to importance: chief or principal.

In context

Best Binocular Reviews0:34

at the most basic level the main purpose of any binocular is to magnify the view and thus bring distant objects more clearly into vision

Binoculars 101: What do the numbers on binoculars mean?

More examples

Our main concern is keeping everyone safe.
The main road runs through the center of town.
Crews are replacing the water main under our street.
We serve roast chicken as the main course.

Forms

main · mains

mainly adverb — For the most part; chiefly.

Similar words

principal: Principal sounds more formal, especially when describing roles or reasons.
primary: Primary emphasizes first importance or priority rather than size.