source: By Ryan Cash of Snowman - Ryan Cash of Snowman, via email, CC BY-SA 3.0

a deep fissure in the earth, rock, or another surface:

(岩･地表などの)大きな切れ目, 亀裂, 谷間(gorge)

e.g. a chasm a mile long

e.g. figurative : he was engulfed in a chasm of despair.

a profound difference between people, viewpoints, feelings, etc.:

〖通例単数形で〗 «…間の» (意見･考えなどの)大きな隔たり, 食い違い «between»

e.g. the chasm between rich and poor.

late 16th century (denoting an opening up of the sea or land, as in an earthquake): from Latin chasma, from Greek khasma ‘gaping hollow’.