(organic chemistry) Forming classification names for classes of organic compounds that contain a carbon skeleton and one or more aromatic rings.

(mathematics, trigonometry) Used to form the names of inverse hyperbolic trigonometric functions, and the symbols for these functions.

Abbreviation of Arabic.

plural of ar

(Greek mythology) The god of war, son of Zeus and Hera, brother Hephaestus, sister Eris, who is his companion. Attended by his sons, (to Aphrodite), Deimos and Phobos, and old war-goddess Enyo.

plural of are

Initialism of acute radiation syndrome. / Initialism of acute retroviral syndrome.

plural of AR

simple past tense and past participle of arr.

present participle of arr.