tert-Butyl alcohol (TBA), also called tert-butanol or 2-methylpropan-2-ol (2M2P), is the simplest tertiary alcohol, with a formula of (CH₃)₃OH (sometimes represented as t-BuOH). It is one of the four isomers of butanol. tert-Butyl alcohol is a clear liquid (or a colorless solid, depending on the ambient temperature) with a camphor-like odor. It is very soluble in water and miscible with ethanol and diethyl ether. It is unique among the isomers of butanol because it tends to be a solid at room temperature, with a melting point slightly above 25 °C.