septenary

From the Latin septēnārius (“consisting of seven each”), from septēnī (“seven each”, “seven at a time”) + -ārius (whence the English suffix -ary).

• (UK) IPA^(key): /sɛpˈtiːnəɹi/

septenary (not comparable)

1. Consisting of or containing seven.
2. Of seventh rank or order.
   • 1899 October, W J McGee, The Beginning of Mathematics, in American Anthropologist 1(4), page 657,

     ... indeed if further evidence than that of bestial and savage counting were required to show that finger-numeration and the quinary system were not primeval, it would be afforded by the development of the senary-septenary system in so many lands.

3. Lasting seven years; continuing seven years.
   • Fuller

     Septenary penance.

• unary (1)
• primary (1st)
• binary (2)
• secondary (2nd)
• ternary (3)
• tertiary (3rd)
• quaternary (4)
• quinary (5)
• senary (6)
• octonary (8)
• nonary (9)
• denary (10)
• duodenary (12)
• vigenary (20)

septenary (plural septenaries)

1. A group of seven things.
2. A period of seven years.
   • 1971, Keith Thomas, Religion and the Decline of Magic, Folio Society 2012, p. 596:

     This idea was based on the doctrine that a man's body changed its character every seven years and that his life was thus made up of ‘septenaries’.

3. (music) The seven notes of the diatonic scale.