What is the origin of 'sleep tight'?
Read moreOne of the mysteries of the English language finally explained.
1A red dyewood obtained from certain tropical American trees of the family Caesalpiniaceae (Leguminosae), especially Caesalpinia echinata.
2The wood of the peach, Prunus persica.
Mid 17th century; earliest use found in Forme Courts of Admiraltie. From peach + wood.