In "if" the title of Kipling's poem is an example of repetition because that same word is repeated throughout the poem. Repetition is when a word or phrase is repeated several times throughout the same text.
The title of the poem "If" begins many of the lines. This shows the importance of trying to follow the speaker's advice: if the son can do all of these things, says the speaker, he will be a man. Repeating "if" also helps the poet stress that nothing is certain in the world.