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

water bed \wa"ter bed`\
   a kind of mattress made of, or covered with, waterproof
   fabric and filled with water, thus providing uniform support
   to the body lying on it; -- also a bed constructed so as to
   contain such a mattress. it is used in hospitals for
   bedridden patients, as well as in some private homes.
   1913 webster +pjc

[2] : WordNet (r) 2.0

water bed
     n : a bed with a mattress made of strong plastic that is filled
         with water

Bed >> B Words
Bed, definition of term: Bed
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Bed Sheet, definition of term: Bed Sheet
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Bed Bug >> B Words
Bed Bug, definition of term: Bed Bug
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Ammonia Water, definition of term: Ammonia Water
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Bed Of Roses >> B Words
Bed Of Roses, definition of term: Bed Of Roses
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