Late 18th century; earliest use found in Philosophical Transactions of the Royal Society of London. From scientific Latin obliquus, use as noun (short for musculus obliquus oblique muscle) of classical Latin oblīquus.
Definition of obliquus in US English:
obliquus
nounə(ʊ)ˈblɪkwəs
Anatomy
More fully "obliquus muscle". An oblique muscle.
Origin
Late 18th century; earliest use found in Philosophical Transactions of the Royal Society of London. From scientific Latin obliquus, use as noun (short for musculus obliquus oblique muscle) of classical Latin oblīquus.