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

sunup \sun"up`\, n.
   sunrise. local, u.s.
   1913 webster

         such a horse as that might get over a good deal of
         ground atwixt sunup and sundown.         --cooper.
   1913 webster

[2] : WordNet (r) 2.0

sunup
     n : the first light of day; "we got up before dawn"; "they
         talked until morning" syn: dawn, dawning, morning,
          aurora, first light, daybreak, break of day, break
         of the day, dayspring, sunrise, cockcrow ant: sunset
see also:
dawn dawning morning aurora first light daybreak 
break of day break of the day dayspring sunrise cockcrow 
sunset 

[3] : Moby Thesaurus II by Grady Ward, 1.0

21 moby thesaurus words for "sunup":
   aurora, break of day, brightening, chanticleer, cockcrow,
   cocklight, crack of dawn, dawn, dawning, day-peep, daybreak,
   daylight, dayspring, first brightening, light, morn, morning,
   peep of day, prime, sunrise, vestibule of day

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