supersessor means someone or something that supersedes another. Lexicurio rates it Rare gem — a strength score of 79 out of 100.
Etymology
From the participle stem of Latin supersedēre (“to supersede”).
noun
- Someone or something that supersedes another.“Lord Wellesley […] sent down all his carriages, servants, staff officers, and general establishment to receive his noble supercessor at the waterside.”