A taxonomic <xref>family</xref> within the <xref>order</xref> <xref>Gentianales</xref> — many <xref>tropical</xref> and <xref>subtropical</xref> <xref>latex</xref>-bearing plants including the <xref>oleander</xref> and <xref>periwinkle</xref>.
User Defined Definitions
"chiefly tropical trees or shrubs or herbs having milky juice and often showy flowers; many are sources of drugs"