Definitions of cloud:

• noun:   a visible mass of water or ice particles suspended at a considerable altitude
• noun:   any collection of particles (e.g., smoke or dust) or gases that is visible
• noun:   out of touch with reality

  Example: "His head was in the clouds"

• noun:   suspicion affecting your reputation

  Example: "After that mistake he was under a cloud"

• noun:   a cause of worry or gloom or trouble

  Example: "The only cloud on the horizon was the possibility of dissent by the French"

• noun:   a group of many insects

  Example: "A cloud of butterflies"

• verb:   billow up in the form of a cloud

  Example: "The smoke clouded above the houses"

• verb:   make milky or dull

  Example: "The chemical clouded the liquid to which it was added"

• verb:   make gloomy or depressed

  Example: "Their faces were clouded with sadness"

• verb:   make overcast or cloudy
• verb:   colour with streaks or blotches of different shades
• verb:   place under suspicion or cast doubt upon
• verb:   make less visible or unclear

  Example: "The stars are obscured by the clouds"

• name:  A surname (common: 1 in 20000 families; popularity rank in the U.S.: #2306)