Tashābuh al-aṭrāf occurs when the ending of an utterance is fittingly related to what it began by presenting. This is not just repetition of an opening word; the closing expression completes or harmonizes with the opening theme.
Semantic congruity is the wider category. Corresponding ends highlight the relation between the beginning and the conclusion. The opening introduces a thought, and the close supplies attributes particularly apt to that thought.
A pleasant rhyme or repeated sound would not be enough unless the final expression belongs meaningfully to the earlier statement.