I. ˈglau̇(-ə)r, ÷ˈglō(-ə)r intransitive verb
Etymology: Middle English (Scots) glowren; akin to Middle Low German glūren to be overcast, Middle Dutch gloeren to leer
Date: 15th century
: to look or stare with sullen annoyance or anger
II. noun
Date: 1715
: a sullen brooding look of annoyance or anger