n 1  :  any of a group of small single-stranded DNA viruses that include the causative agent of erythema infectiosum  2  :  a highly contagious febrile disease of dogs that is caused by a parvovirus, is spread esp. by contact with infected feces, and is marked by loss of appetite, lethargy, often bloody diarrhea and vomiting, and sometimes death - called also parvo  .
 
 
 
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