first letter of the Roman alphabet, based on Greek alpha (see alpha). In music from c. 1600 as the name of the sixth note of the natural scale; it is the note given by a fixed-tone instrument (usually oboe or organ) to which all the instruments of an orchestra are tuned. As a blood type, 1926, denoting A agglutinogens. The A side of a two-sided record (by 1962, see side (n.)) held the material chosen for promotion. A-bomb, short for atom bomb, was in newspaper headlines by Aug. 8, 1945.

also AA, abbreviation of Alcoholics Anonymous, attested by 1941, American English. The group name was the title of a book published in 1938 by the founder, Bill W. From 1914 as an abbreviation of anti-aircraft guns.

masc. proper name, in the Old Testament the brother of Moses, from Hebrew Aharon, which is said to be probably of Egyptian origin. The Arabic form is Harun. Related: Aaronic. Aaron's beard as a popular name for various plants (including St. John's wort and a kind of dwarf evergreen) deemed to look hairy in some way is from 1540s. Aaron's rod is from 1834 in botany, 1849 in ornamentation; the reference is biblical (Exodus vii.19, etc.).

affixed to a name, abbreviation of Modern Latin Artium Baccalaureus "Bachelor of Arts" (see bachelor), 1773, American English. British English preferred B.A., perhaps because A.B. was used in Britain to mean able-bodied on seamen's papers.

Swedish pop music group formed 1972, the name dates from 1973 and is an acronym from the first names of the four band members: Anni-Frid Lyngstad, Björn Ulvaeus, Benny Andersson, Agnetha Fältskog.

dynasty of caliphs of Baghdad (C.E. 750-1258) claiming descent from Abbas (566-652), uncle of the Prophet. His name is from the same Semitic source as abbot. With patronymic suffix.

element in many Arabic names, from Arabic (Semitic) abd "slave, servant," as in Abdallah "servant of God."

masc. proper name, in the Old Testament the second son of Adam and Eve, from Hebrew Hebhel, literally "breath," also "vanity;" "so called from his short life and sudden death" [Thayer].

also Abnaki, Algonquian people and language of northern New England and eastern Canada, 1721, from French abenaqui, from the people's name, East Abenaki wapanahki, literally "person of the dawn-land," hence "easterners." [Bright]

fem. proper name, from Hebrew Abhigayil, literally "my father is rejoicing," from abh "father" + gil "to rejoice." In the Old Testament Abigail the Carmelitess was a wife of David. Used in general sense of "lady's maid" (1660s) from character of that name in Beaumont & Fletcher's "The Scornful Lady." Her traditional male counterpart was Andrew. The waiting maid association perhaps begins with I Samuel xxv, where David's wife often calls herself a "handmaid."