wheat vs bulgur wheat

wheat and bulgur wheat both are nouns.

Word	Noun	Adjective	Verb	Adverb
wheat	Yes	No	No	No
bulgur wheat	Yes	No	No	No

As nouns, bulgur wheat is a hyponym of wheat; that is, bulgur wheat is a word with a more specific, narrower meaning than wheat:

wheat: grains of common wheat; sometimes cooked whole or cracked as cereal; usually ground into flour
bulgur wheat: parched crushed wheat

Other hyponyms of wheat include bulghur, bulgur, cracked wheat.

wheat (noun)	bulgur wheat (noun)
a variable yellow tint; dull yellow, often diluted with white	parched crushed wheat
grains of common wheat; sometimes cooked whole or cracked as cereal; usually ground into flour
annual or biennial grass having erect flower spikes and light brown grains