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

rain \rain\, v. i. imp.  p. p. rained r=and; p. pr. 
   vb. n. raining. as. regnian, akin to g. regnen, goth.
   rignjan. see rain, n.
   1. to fall in drops from the clouds, as water; -- used mostly
      with it for a nominative; as, it rains.
      1913 webster

            the rain it raineth every day.        --shak.
      1913 webster

   2. to fall or drop like water from the clouds; as, tears
      rained from their eyes.
      1913 webster
see also:
rained raining rain 

[2] : WordNet (r) 2.0

raining
     adj : falling in drops or as if falling like rain; "watched the
           raining apple blossoms"

Raining >> R Words
Raining, definition of term: Raining
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