grandrelation means A member of one's family from whom one is separated by two generations. Lexicurio rates it Rare gem — a strength score of 84 out of 100.
Etymology
From grand- + relation.
noun
- A member of one's family from whom one is separated by two generations.“This includes bilateral name relations, consanguineal-affinal term transpositions, reciprocal grandrelation and sibling-cohort terms, extension of relationship terms through namesake equivalence, and marriage to specific cousin categories.”