Reduplication

Definition:

(n.) The act of doubling, or the state of being doubled.
(n.) A figure in which the first word of a verse is the same as the last word of the preceding verse.
(n.) The doubling of a stem or syllable (more or less modified), with the effect of changing the time expressed, intensifying the meaning, or making the word more imitative; also, the syllable thus added; as, L. tetuli; poposci.

Compare reduplication with other words:

deduplication vs. reduplication