Viscosity refers to the resistance to flow in a liquid. The intermolecular attractions between molecules in a liquid affect its viscosity. When the intermolecular forces of attraction are strong within a liquid, there is a larger viscosity. Alcohols have hydrogen bonding which are typically much stronger attractions than ordinary dipole moments. Therefore, its viscosity is high. Also, a group of ethanol molecules is much harder to separate from each other than a group of ether molecules.