Dark Navy Blue
noun
Put a thick drop of navy blue paint on a canvas and it will look like an even bolder dark navy blue.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
黒と濃紺のスーツが一着ずつあると便利ですよ。
Having one black and one dark navy blue suit is convenient.