grape sugar

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Dextrose obtained from grapes.

Century Dictionary and Cyclopedia

1. n. Same as dextrose.

GNU Webster's 1913

1. n. See Glucose.
2. n. a sirupy or white crystalline sugar (dextrose or glucose) found as a characteristic ingredient of ripe grapes, and also produced from many other sources. See Dextrose, and Glucose.

WordNet 3.0

1. n. an isomer of glucose that is found in honey and sweet fruits