DuckCorp Dico

Found one definition

1.                 From English - German Ding/FreeDict dictionary ver. 1.9-fd1:
                   
   
   
                   
                     
   i-spin /ˈaɪ spˈɪn/
   Isotopenspin <masc>, Isospin <masc>, isobarer Spin <masc> [techn.]
            Note: Kerntechnik
      Synonym: isotopic spin
            Note: nuclear engineering