Compound having the general formula
\(\ce{RCH(OH)(OR^{\prime})}\) (
\(\ce{R^{\prime}} \neq \ce{H}\)).
Note: A hemiacetal results from the nucleophilic addition of a hydroxy group to a carbonyl functionality of an aldehyde, as in ring closure of an aldose.
See: anomeric hydroxy group, hemiketal
Source:
PAC, 2018, 90, 1121. 'Terminology of bioanalytical methods (IUPAC Recommendations 2018)' on page 1174 (https://doi.org/10.1515/pac-2016-1120)