septuagenarian

The story

1. Latin · derived fromseptuāginta“seven tens, 70”
2. Latin · derived fromseptuagenus“70 each”
3. French · derived fromseptuagénaire
4. Latin · borrowed fromseptuagenarius“containing 70”
5. English todayseptuagenarian

From Latin septuagenarius (“containing 70”) + -an (suffix forming adjectives and representative nouns), either directly or via French septuagénaire, from Latin septuagenus (“70 each”) + -arius (“-ary”), from Latin septuāginta (“seven tens, 70”).

Words from the same roots