The structure obtained by removing the hydroxy group from the hemiacetal function of a monosaccharide and, by extension, of a lower oligosaccharide.
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1338 (https://doi.org/10.1351/pac199567081307)