OL may refer to:
Old English (Ænglisc, Anglisc, Englisc, pronounced [ˈæŋɡliʃ]), or Anglo-Saxon, is the earliest historical form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages.
Olivia Newton-John, (born 26 September 1948) is an English-born Australian singer, songwriter, actress, entrepreneur, dancer, and activist.
Olanzapine, sold under the trade name Zyprexa among others, is an atypical antipsychotic primarily used to treat schizophrenia and bipolar disorder.
An organic light-emitting diode (OLED or Organic LED), also known as an organic EL (organic electroluminescent) diode, is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound that emits light in response to an electric current.
Oliver Cromwell (25 April 1599 – 3 September 1658) was an English military and political leader. He served as Lord Protector of the Commonwealth of England, Scotland, and Ireland "and of the dominions thereto belonging" from 1653 until his death, acting simultaneously as head of state and head of government of the new republic.
Sir Oliver Letwin, (born 19 May 1956) is a British politician who has served as the Member of Parliament (MP) for West Dorset since 1997. Letwin sits as an independent, having been elected as a member of the Conservative Party before having the whip removed in September 2019. He served as Shadow Chancellor of the Exchequer under Michael Howard and Shadow Home Secretary under Iain Duncan Smith.
Old Norse was a North Germanic language that was spoken by inhabitants of Scandinavia and their overseas settlements from about the 9th to the 13th centuries.
The olive, known by the botanical name Olea europaea, meaning "European olive", is a species of small tree in the family Oleaceae, found in the Mediterranean Basin from Portugal to the Levant, the Arabian Peninsula, and southern Asia as far east as China, as well as the Canary Islands and Réunion.