(astronomy) A small autumn constellation of the northern sky, said to resemble an arrow. It lies between the constellations of Vulpecula and Aquila.

(law enforcement) internal affairs department / (robotics) intelligent assist device / (neurology, pathology) Initialism of Internet addiction disorder.

(pharmacology) A particular antiviral drug.

(medicine) A very rare disorder in which the patient sweats blood and/or blood pigments, usually resulting from extreme physical and/or mental stress. / Bloody sweat; sweating blood.