concentric

adjective2

1. •
   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. — 2020
2. •
   Of a motion, in the direction of contraction of a muscle. (e.g. the extension of the lower arm by means of the elbow joint while contracting the triceps and other elbow extensor muscles; closing of the jaw while flexing the masseter).