[1] : The Collaborative International Dictionary of English v.0.48

sempiternal \sem`piter"nal\, a. l. sempiternus, fr. semper
   always: cf. f. sempiternel.
   1. of neverending duration; everlasting; endless; having
      beginning, but no end. --sir m. hale.
      1913 webster

   2. without beginning or end; eternal. --blackmore.
      1913 webster

[2] : WordNet (r) 2.0

sempiternal
     adj : having no known beginning and presumably no end; "the
           dateless rise and fall of the tides"; "time is
           endless"; "sempiternal truth" syn: dateless, endless
see also:
dateless endless 

Sempiternal >> S Words
Sempiternal, definition of term: Sempiternal
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