Repetition & Refrain
Conduplicatio
Repeating a key word from one sentence prominently in the next. Repeating the full word, instead of using a pronoun, keeps attention on that idea.
"This afternoon, this Easter afternoon, I saw a friend die. A friend I had known…"
Don't confuse it with Anadiplosis. Anadiplosis requires the repeat at the exact seam (last word → first word); conduplicatio just needs the key word to recur early in the next unit.
Examples
Trust made the agreement possible. Without trust, no signature would have mattered.
The key word “trust” is repeated prominently in the next sentence; it does not sit at an end-to-start seam.
The rest of the family
Anaphora Epistrophe Symploce Epanalepsis Anadiplosis Gradatio / Climax Epizeuxis Diacope Polyptoton