septennial

[ sep-ten-ee-uh l ]
/ sɛpˈtɛn i əl /

adjective

occurring every seven years.
of or for seven years.

noun

something that occurs every seven years.

Origin of septennial

1630–40; < Late Latin septenni(s) (Latin septuennis) seven years old (sept(em) seven + -enn-, combining form of annus year + -is adj. suffix) + -al1
Related formssep·ten·ni·al·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for septennial

British Dictionary definitions for septennial

septennial

/ (sɛpˈtɛnɪəl) /

adjective

occurring every seven years
relating to or lasting seven years
Derived Formsseptennially, adverb

Word Origin for septennial

C17: from Latin septennis, from septem seven + annus a year
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012