Definition from Wiktionary, the free dictionary
irroration (plural irrorations)
- (obsolete) A sprinkling or wetting with dew.
- (chiefly entomology) Markings reminiscent of spots or dew drops.
1907, L. Colonel, C.T. Bingham, The Fauna Of British India, page 239:
- Underside: ground-colour similar, both fore and hind wings with extensive irroration of black scale which varies considerably in amount: in some specimens it is very dense and gives a glackish tint to the ground-colour, especially on the hind wing.
1952, Alexey Diakonoff, Microlepidoptera of New Guinea, page 100:
- Black, markings formed by pale blue glossy irroration; markings white on costal edge.
1969, J. F. Clarke, Exotic microlepidoptera, page 32:
- […] costa with whitish strigulæ separated by dark fuscous or blackish irroration […]