primary

noun

1.
a preliminary election where delegates or nominees are chosen
primary election
2.
one of the main flight feathers projecting along the outer edge of a bird's wing
primary feather primary quill
3.
(astronomy) a celestial body (especially a star) relative to other objects in orbit around it
4.
coil forming the part of an electrical circuit such that changing current in it induces a current in a neighboring circuit
primary coil primary winding