Adar is a month of the Hebrew calendar. In leap years there is a month Adar I and a month Adar II. Adar (Mandaean month) is also a month of the Mandaean calendar.

Adar may also refer to:

• `Adar, a village in Yemen
• Adar, Iran, a village in Iran
• Adar River in the state of Upper Nile, South Sudan
• Adar oilfield in South Sudan

• Adar (surname)
• Atar or Adar, a Middle Persian term for Zoroastrian fire
• ADAR, a type of Adenosine deaminase acting on RNA
• Adar (Mandaean month), a month of the Mandaean calendar
• Adar (Star Wars), a creature in the Star Wars universe
• "Adar" (The Lord of the Rings: The Rings of Power), an episode of the first season of The Lord of the Rings: The Rings of Power
  • The character introduced in the same episode of the show