Definitions of dawn:

• noun:   the earliest period

  Example: "The dawn of civilization"

• noun:   the first light of day

  Example: "We got up before dawn"

• noun:   an opening time period

  Example: "It was the dawn of the Roman Empire"

• verb:   appear or develop

  Example: "The age of computers had dawned"

• verb:   become light

  Example: "It started to dawn, and we had to get up"

• verb:   become clear or enter one's consciousness or emotions

  Example: "It dawned on him that she had betrayed him"

• name:  A female given name (common: 1 in 495 females; popularity rank in the U.S.: #105)
• name:  A surname (very rare: popularity rank in the U.S.: #19735)