Use the noun repetition to describe something that is repeated over and over, like the repetition of singing the alphabet song several times a day to help young children learn the letters.
To correctly pronounce repetition, accent the third syllable: "re-peh-TIH-shun." Repetition and the closely related repeat come from the Latin word repetere, meaning "do or say again." It can be a very effective tool in public speaking, such as the repetition of "I have a dream that one day . . ." in Dr. Martin Luther King Jr.'s famous speech.