ODM2 Variable Name Controlled Vocabulary ODM2 Working Group A vocabulary for describing the name of Variables. 2,3,4,6-Tetrachlorophenol 2,3,4,6-Tetrachlorophenol (C6H2Cl4O) Originally from the CUAHSI HIS VariableNameCV. See: http://his.cuahsi.org/mastercvreg/edit_cv11.aspx?tbl=VariableNameCV.