WordNet (r) 3.0 (2006):

Rh
    n 1: a blood group antigen possessed by Rh-positive people; if
         an Rh-negative person receives a blood transfusion from an
         Rh-positive person it can result in hemolysis and anemia
         [syn: rhesus factor, Rh factor, Rh]
    2: a white hard metallic element that is one of the platinum
       group and is found in platinum ores; used in alloys with
       platinum [syn: rhodium, Rh, atomic number 45]
    3: any of several hormones produced in the hypothalamus and
       carried by a vein to the anterior pituitary gland where they
       stimulate the release of anterior pituitary hormones; each of
       these hormones causes the anterior pituitary to secrete a
       specific hormone [syn: releasing hormone, RH, releasing
       factor, hypothalamic releasing hormone, hypothalamic
       releasing factor]

V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

RH
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