Oceanus Procellarum

[ oh-see-ah-nuh s proh-suh-lahr-uh m, -an-uh s, oh-shee- ]
/ ˌoʊ siˈɑ nəs ˌproʊ səˈlɑr əm, -ˈæn əs, ˌoʊ ʃi- /

noun

(Ocean of Storms) the largest dark plain on the face of the moon, in the second and third quadrants: about 2 million square miles (5.2 million sq. km).