hyperglycemia Syllabification: (hy·per·gly·ce·mi·a)Pronunciation: /ˌhīpərglīˈsēmēə/ (Britishhyperglycaemia)Definition of hyperglycemia noun Medicine an excess of glucose in the bloodstream, often associated with diabetes mellitus. Derivatives hyperglycemicPronunciation: /-ˈsēmik/ adjective Origin: late 19th century: from hyper- 'above normal' + glyco- + -emiahyperglycemia in other Oxford dictionaries Definition of hyperglycemia in the British & World English dictionary