hexagramPronunciation: /ˈhɛksəgram/Definition of hexagram noun a figure formed of six straight lines, in particular: a star-shaped figure formed by two intersecting equilateral triangles. any of a set of sixty-four figures made up of six parallel whole or broken lines, occurring in the ancient Chinese I Ching. Origin: mid 19th century: from hexa- 'six' + Greek gramma 'line'hexagram in other Oxford dictionaries Definition of hexagram in the US English dictionary