the major component of starch (about 80 per cent), consisting of branched chains of glucose units. It is insoluble and gives a red-brown colour with iodine
Compare amylose
amylopectin in American English
(ˌæməloʊˈpɛktɪn)
noun
a nearly insoluble substance derived from the outer part of starch granules: it is a polymer of glucose