TROPIC

I. noun Etymology: Middle English tropik, from Latin ~us of the solstice, from Greek tropikos, from tropē turn Date: 1527 either of the two parallels of terrestrial latitude at a distance of about 23 1/2 degrees north or south of the equator where the sun is directly overhead when it reaches its most northerly or southerly point in the sky, the region lying between the ~s, II. adjective Date: 1551 of, relating to, or occurring in the ~s, III. adjective Etymology: trop- Date: 1903 of, relating to, or characteristic of tropism or of a tropism, influencing the activity of a specified gland