Origin of seventyMiddle English seofentig ; from Old English (hund)seofontig: see seven and amp; -ty
- The cardinal number equal to 7 × 10.
- seventiesa. A decade or the numbers from 70 to 79: They became grandparents in their seventies. The temperature hovered in the seventies.b. often Seventies The decade from 70 to 79 in a century.
Origin of seventyMiddle English, from Old English -seofontig (in hundseofontig, the decade seventy, seventy); see sept&mlowring; in Indo-European roots.