Astron. (a) The point in the sky directly overhead, the zenith; also, the part of an astrolabe representing the zenith; (b) the azimuth reading or bearing of a heavenly body.
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(a) An indication; proof, evidence; a characteristic, mark; (b) in signe of, as a token of (sth.), as an indication of (sth.); also, as a testimony to (sth.), as a memento of (sth.); in signe that, to……