Zeta

from WordNet (r) 3.0 (2006)
zeta
    n 1: the 6th letter of the Greek alphabet
    
from The Collaborative International Dictionary of English v.0.48
Zeta \Ze"ta\, n. [L., from Gr. ?. Cf. {Zed}.]
   A Greek letter [[zeta]] corresponding to our z.
   [1913 Webster]
    

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