great millet vs sorghum

great millet and sorghum both are nouns.

Word	Noun	Adjective	Verb	Adverb
great millet	Yes	No	No	No
sorghum	Yes	No	No	No

As nouns, sorghum is a hypernym of great millet; that is, sorghum is a word with a broader meaning than great millet:

great millet: important for human and animal food; growth habit and stem form similar to Indian corn but having sawtooth-edged leaves
sorghum: economically important Old World tropical cereal grass

great millet (noun)	sorghum (noun)
important for human and animal food; growth habit and stem form similar to Indian corn but having sawtooth-edged leaves	made from juice of sweet sorghum
	economically important Old World tropical cereal grass