What is the origin of 'sleep tight'?
Read moreOne of the mysteries of the English language finally explained.
A ribbon worm (nemertean) of the order Palaeonemertea (class Anopla).
Of or relating to the order Palaeonemertea (class Anopla) of ribbon worms.
Late 19th century; earliest use found in George Rolleston (1829–1881), physician and physiologist. From scientific Latin Palaeonemertea, order name + -an, after nemertean.