cerulean

noun

1. (countable, uncountable)A greenish-blue color.

   “For our blues we have the azures and ceruleans, lapis lazulis, the light and dusty, the powder blues, the deeps: royal, sapphire, navy, and marine […]”

2. (countable)Any of various lycaenid butterflies of the genus Jamides.

adj

1. Sky-blue.

   “As far to the west as Monica could see, her world was a sea of fog, […]. Above it arched a cerulean sky; as the sun climbed to the zenith, […], the fog gradually took on a bluish tinge.”

   “Oh Ramona, if there was only some kind of future / And these cerulean skies / Something in our skies, something in our skies”

   “But what you don't know is that that sweater is not just blue, it's not turquoise, it's not lapis, it's actually cerulean. And you're also blithely unaware of the fact that in 2002, Oscar de la Renta did a collection of cerulean gowns. And then I think it was Yves Saint Laurent, wasn't it, who showed cerulean military jackets?”