(1):

(n.) Certain prayers to be repeated at stated times of the day, as matins and vespers.

(2):

(n.) A measure of distance traveled.

(3):

(n.) The time of the day, as expressed in hours and minutes, and indicated by a timepiece; as, what is the hour? At what hour shall we meet?

(4):

(n.) The twenty-fourth part of a day; sixty minutes.

(5):

(n.) Fixed or appointed time; conjuncture; a particular time or occasion; as, the hour of greatest peril; the man for the hour.