https://doi.org/10.1351/goldbook.G02654
Dihydric @A00204@, also known as @D01748@, in which the two hydroxy groups are on different carbon atoms, usually but not necessarily adjacent. E.g. HOCH2CH2OH 'ethylene glycol' (ethane-1,2-diol), HO[CH2]4OH butane-1,4-diol.