octonary

[ok-tuh-ner-ee] /ˈɒk təˌnɛr i/
adjective
1.
pertaining to the number 8.
2.
consisting of eight.
3.
proceeding by eight.
4.
octal (def 1).
noun, plural octonaries.
5.
a group of eight; an ogdoad.
6.
Also, octal. Prosody. a stanza of eight lines.
7.
a number in an octonary system.
Origin
1525-35; < Latin octōnārius consisting of eight, equivalent to octōn(ī) eight each + -ārius -ary
British Dictionary definitions for octonary

octonary

/ˈɒktənərɪ/
adjective
1.
relating to or based on the number eight
noun (pl) -naries
2.
(prosody) a stanza of eight lines
3.
a group of eight
Word Origin
C16: from Latin octōnārius, from octōnī eight at a time