"Bluelashed" means "having blue eyelashes," likely likening the pale blue lines on the body to eyelashes.
The Japanese name refers to the moon — the black circular marking surrounded by a pale blue ring is likened to the moon.
It is also known as the Eclipse butterflyfish in English, with "eclipse" referring to a lunar or solar eclipse. The black circle bordered by a pale blue ring resembles the appearance of a lunar eclipse.
