Dawn

Concise Oxford English Dictionary © 2008 Oxford University Press:
dawn/dɔːn/

▶noun

• 1 the first appearance of light in the sky before sunrise.

• 2 the beginning of something: the dawn of civilization.

▶verb

• 1 (of a day) begin.

  ■ come into existence.

• 2 (often dawn on) become evident or understood.

– origin C15 (as v.): back-form. from dawning.