Hemicellulose

noun

1. Any of several polysaccharides that are more complex than a sugar and less complex than cellulose, found in plant cell walls and produced commercially from corn grain hulls.
2. A form of cellulose which is easily hydrolyzed by dilute acids and readily attacked by certain enzyms.
3. a mixture of several plant polysaccharides, of smaller molecular weight than cellulose, that are soluble in dilute alkali; they are involved in the manufacture of paper, and are used in the production of furfural and ethanol