Definitions of hour:

• noun:   distance measured by the time taken to cover it

  Example: "We live an hour from the airport"

• noun:   a period of time equal to 1/24th of a day

  Example: "The job will take more than an hour"

• noun:   clock time

  Example: "The hour is getting late"

• noun:   a special and memorable period

  Example: "It was their finest hour"