A northern geometrid moth, Venusia cambrica, with pale wings marked with wavy brown lines, and caterpillars that feed on the leaves of rowan (Sorbus aucuparia).
Origin
Mid 19th century; earliest use found in William Wood (1774–1857), conchologist and bookseller.
Definition of Welsh wave in US English:
Welsh wave
noun
A northern geometrid moth, Venusia cambrica, with pale wings marked with wavy brown lines, and caterpillars that feed on the leaves of rowan (Sorbus aucuparia).
Origin
Mid 19th century; earliest use found in William Wood (1774–1857), conchologist and bookseller.