What is the origin of 'sleep tight'?
Read moreOne of the mysteries of the English language finally explained.
1The wood of the pear tree, Pyrus communis.
2Chiefly with distinguishing word: the wood of any of several African trees, especially (in full "African pearwood") that of Manilkara obovata and Minus djave (both family Sapotaceae).
Mid 18th century; earliest use found in Nathan Bailey (d. 1742), lexicographer and schoolmaster. From pear + wood.