coil forming the part of an electrical circuit such that changing current in it induces a current in a neighboring circuit; "current through the primary coil induces current in the secondary coil"
of first rank or importance or value; direct and immediate rather than secondary; "primary goals"; "a primary effect"; "primary sources"; "a primary interest"
most important element; "the chief aim of living"; "the main doors were of solid glass"; "the principal rivers of America"; "the principal example"; "policemen were primary targets"; "the master bedroom"; "a master switch"