1. The point on the celestial sphere that is directly above the observer.
2. The upper region of the sky.
3. The highest point above the observer's horizon attained by a celestial body.
4. The point of culmination; the peak: the zenith of her career. See Synonyms at summit.
[Middle English senith, from Old French cenith, from Medieval Latin, from Arabic samt (ar-ra's), path (over the head), from Latin sēmita, path; see mei-1 in the Appendix of Indo-European roots.]
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