pri·ma·ry / ˈprīˌmerē; ˈprīm(ə)rē/ • adj. 1. of chief importance; principal: the government's primary aim is to see significant reductions in unemployment.2. earliest in time or order of development: the country was in the primary stage of socialism. ∎  not derived from, caused by, or based on anything else: the research involved the use of primary source materials in national and local archives.3. of or relating to education for children between the ages of about five and ten: a primary school.4. Biol. & Med. belonging to or directly derived from the first stage of development or growth: a primary bone tumor.5. (Primary) Geol. former term for Paleozoic.6. relating to or denoting the input side of a device using electromagnetic induction, esp. in a transformer.7. Chem. (of an organic compound) having its functional group located on a carbon atom that is bonded to no more than one other carbon atom. ∎  (chiefly of amines) derived from ammonia by replacement of one hydrogen atom by an organic group.• n. (pl. -ries) 1. (also primary election) a preliminary election to appoint delegates to a party conference or to select the candidates for a principal, esp. presidential, election.2. short for: ∎  a primary color. ∎  Ornithol. a primary feather. ∎  a primary coil or winding in an electrical transformer.3. Astron. the body orbited by a smaller satellite or companion.4. (the Primary) dated Geol. the Primary or Paleozoic era.

primary One of the outer flight feathers of birds, which originate from the manus. Most non-passerines have 10 primaries. Ciconiidae (storks), Phoenicopteridae (flamingos), and Podicipedidae (grebes) have 12; Ardeidae (herons), Anatidae (ducks, geese, etc.), and some other groups have 11. Most passerines have nine functional primaries, the tenth being reduced.

primary Method used in the USA to select candidates for an election, in effect an election among the members of a political party. In a direct primary, the commonest type, any number of party members may stand and are voted for in a ballot of all the members. In an open primary, all the parties in an election are involved, and the voter votes for both the party and candidate of his or her choice. In a presidential election year, most US states select delegates to the national party convention in a presidential primary, the delegates having announced which presidential candidate they support.

primary earliest, original XV; of the first rank XVI; of the first order or stage XVII. — L. prīmārius chief, principal, f. prīmus PRIME2; see -ARY.