concentric

Etymology

From Middle English concentrik, from Middle French concentrique, from Medieval Latin concentricus, from Latin con- (“with, together”) + centrum (“circle, center”). Equivalent to con- + -centric.

adj

1. (geometry) Having a common center.
   Seven huge concentric semi-circular rings of stone surround the northern end, and quite rightly are Grade 2-listed by conservation body Historic England. August 26 2020, Tim Dunn, “Great railway bores of our time!”, in Rail, page 45
2. (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).