adj. 1. Occurring every seven years. 2. Consisting of or continuing for seven years. n. An event that occurs every seven years. [From Late Latin septennium, period of seven years, from Latin septennis, of seven years : septem, seven; see sept in the Appendix of Indo-European roots + annus, year; see at- in the Appendix of Indo-European roots.] sep·tenni·al·ly adv. |
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.