What is the origin of 'sleep tight'?
Read moreOne of the mysteries of the English language finally explained.
An oily liquid which is present in coal tar, used in the preparation of a variety of pharmaceuticals and dyes and as a sedative in the handling and transport of fish.
Late 19th century; earliest use found in Journal of the Chemical Society. From quin- + ald- + -ine, after German Chinaldin.