ze·nith / ˈzēni[unvoicedth]/ • n. [in sing.] the highest point reached by a celestial or other object: the missile reached its zenith and fell. ∎ the point in the sky or celestial sphere directly above an observer.The opposite of nadir. ∎ the time at which something is most powerful or successful: under Justinian, the Byzantine Empire reached its zenith of influence.
DERIVATIVES: ze·nith·al / -nə[unvoicedth]əl/ adj.
zenith, in astronomy, the point in the sky directly overhead; more precisely, it is the point at which the celestial sphere is intersected by an upward extension of a plumb line from the observer's location. Its position in the sky thus depends on the direction of the earth's gravitational field at the observer's location. The zenith is a reference point in the altazimuth coordinate system; its altitude above the celestial horizon is 90°. The angular distance from the zenith to a celestial body is called the zenith distance. The nadir, directly opposite the zenith, has a zenith distance of 180°; the celestial horizon has a zenith distance of 90°.
, outwith, pith, smith
•twentieth • seventieth • eightieth
•fiftieth • sixtieth • ninetieth
•fortieth • thirtieth • Edith • Judith
•Meredith • Griffith • Hesketh
•tallith • Delyth • Lilith • megalith
•monolith • blacksmith • Nasmyth
•tinsmith • Ladysmith • locksmith
•songsmith • goldsmith • gunsmith
•coppersmith • silversmith
•Gwyneth • Lapith • Hollerith
•Asquith • Sopwith
point of the sky directly overhead, †point of the horizon at which a heavenly body rises XIV; highest point or state XVII. ME. cenyth
— OF. cenit
) or medL. cenit
, obscurely — Arab. samt
in samt ar-ra's
‘path over the head’ (samt
the highest point reached by a celestial or other object; the point in the sky or celestial sphere
directly above an observer; in figurative usage, the time at which something is most powerful or successful. Recorded from late Middle English, the word comes via Old French from medieval Latin cenit
, based on Arabic samt (ar-ra's)
‘path (over the head)’.
In astronomy, point on the celestial sphere
that is directly overhead. The zenith distance of a heavenly body is the angle it makes with the zenith. It is diametrically opposite the nadir
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