What is the origin of 'sleep tight'?
Read moreOne of the mysteries of the English language finally explained.
1A person who or thing which aggravates.
2Slang. A greased lock of hair, especially one worn over the temple or forehead. Compare "lovelock", Newgate knocker. Now historical.
Late 16th century; earliest use found in John Florio (1553–1625), author and teacher of languages. From aggravate + -or, originally after Italian gravatore.