1818 J. Keats ii. 58 Fish, Golden, or rainbow-sided.
1820 J. Keats Lamia i, in 6 So rainbow-sided, touch'd with miseries, She [sc. a snake] seem'd, at once, some penanced lady elf.
1998 (Nexis) 6 Sept. (Sunday Mag.) 8 The rainbow-sided steelhead trout spawn in the Grand in the fall, winter and early spring.