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

cretaceous \creta"ceous\ kr-et=a"shu^s, a. l.
   cretaceus, fr. creta chalk. see crayon.
   1. having the qualities of chalk; abounding with chalk;
      chalky; as, cretaceous rocks and formations. see chalk.
      1913 webster

   2. geol. of, pertaining to, or designating, the period of
      time following the jurassic and preceding the tertiary,
      generally given as from 144 million years b. p. to 65
      million years b. p.. also called
see also:
crayon chalk 

[2] : WordNet (r) 2.0

cretaceous
     adj 1: abounding in chalk
     2: of or relating to the cretaceous geologic era; "cretaceous
        rocks"
     n : from 135 million to 63 million years ago; end of the age of
         reptiles; appearance of modern insects and flowering
         plants syn: cretaceous period
see also:
cretaceous period 

Cretaceous >> C Words
Cretaceous, definition of term: Cretaceous
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