Definitions of blur:

• noun:   a hazy or indistinct representation

  Example: "It happened so fast it was just a blur"

• verb:   to make less distinct or clear

  Example: "The haze blurs the hills"

• verb:   become vague or indistinct

  Example: "The distinction between the two theories blurred"

• verb:   make dim or indistinct

  Example: "The drug blurs my vision"

• verb:   make unclear, indistinct, or blurred
• verb:   make a smudge on; soil by smudging
• verb:   become glassy; lose clear vision