iridianadj.

/ʌɪˈrɪdɪən/Etymology: < Latin īrid- iris n. + -ian suffix.
the world > matter > colour > variegation > [adjective] > as rainbow
1884 in IV.
1888 A. Upward 146 ii Truth's iridian arch.
This entry has not yet been fully updated (first published 1900; most recently modified version published online March 2018).