blue
n. C / U A1 Beginner Oxford US //ˈbɫu// UK //blˈuː// blue
n. the color of a clear sky or the deep sea.
n. a primary color between green and violet in the visible spectrum. Uncountable when referring to the color as an abstract concept, but countable when referring to specific shades.
Her favorite color is blue.
He painted the walls of his bedroom a calming shade of blue.
The artist used various shades of blue to evoke a sense of deep melancholy and infinite space.
From the German surname, Americanized from Blau or its French cognate Bleu.
Usage
Functions as a noun to name the color itself. More commonly used as an adjective to describe an object's color (e.g., 'a blue car').