Aha

AHA may refer to:

• AHA! A Hands-On Adventure, a children's museum in Lancaster, Ohio
• Alpha Hydroxy Acid
• Amateur Hockey Association
• American Heart Association
• American Hebrew Academy
• American Historical Association
• American Hockey Association:
  • American Hockey Association (1926–1942)
  • American Hockey Association (1992–1993)
• American Homebrewers Association
• American Hospital Association
• American Humane Association
• American Humanist Association
• Arabian Horse Association
• Asian Hotel Alliance
• Association of Hispanic Arts
• Atlantic Hockey Association
• Australian Hotels Association
• Australian Historical Association
• Australian Hypnotherapists Association
• Autoimmune hemolytic anemia (more commonly abbreviated AIHA)

Aha may also refer to:

• Aha experience, (from German Aha-Erlebnis) an insight that manifests itself suddenly
• a-ha, Norwegian pop music band
• Aha (god), in ancient Egyptian theology
• Aha (spirit), a female spirit in Yakut myth who is the guardian of rivers
• One of two figures in the Book of Mormon: Aha (Book of Mormon), a Nephite soldier, and Ahah (Book of Mormon) a Jaredite
• Hor-Aha, Egyptian Pharaoh
• Aha ha, a species of wasp
• "Aha", an Egyptian phrase found on the Rhind Papyrus used to indicate an unknown quantity; a substitute for the variable letter x.
• Aha !, poetry by Aleister Crowley