(physiology) (of a motion) In the direction of contraction of a muscle. (E.g. extension of the lower arm via the elbow joint while contracting the triceps and other elbow extensor muscles; closing of the jaw while flexing the masseter).
Antonym: eccentric. Concentric and eccentric movements are collectively referred to as isotonic (with motion), the antonym of which is isometric (without motion).
Origin of concentric
Middle English, from Middle French concentrique, from Medieval Latin concentricus, from Latincon- (“with, together”) + centrum (“circle, center”)
"Concentric circles throw off the creatures pursuing us," he reminded her.
The concentric castle, with its rings of walls, began to displace the old keep and bailey with.
Sometimes the activity of the successive cambiums simply results in the formation of concentric rings or arcs of secondary xylem and phloem.
capacity of two concentric spheres, of two coaxial cylinders and of two parallel planes.
Thus the core of a circle or an ellipse is a concentric circle or ellipse of one quarter the size.