bean vs soya bean

bean and soya bean both are nouns.

Word	Noun	Adjective	Verb	Adverb
bean	Yes	No	Yes	No
soya bean	Yes	No	No	No

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

bean: any of various edible seeds of plants of the family Leguminosae used for food
soya bean: the most highly proteinaceous vegetable known; the fruit of the soybean plant is used in a variety of foods and as fodder (especially as a replacement for animal protein)

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

bean: any of various seeds or fruits that are beans or resemble beans
soya bean: a source of oil; used for forage and soil improvement and as food

bean (noun)	soya bean (noun)
informal terms for a human head	the most highly proteinaceous vegetable known; the fruit of the soybean plant is used in a variety of foods and as fodder (especially as a replacement for animal protein)
any of various edible seeds of plants of the family Leguminosae used for food	erect bushy hairy annual herb having trifoliate leaves and purple to pink flowers; extensively cultivated for food and forage and soil improvement but especially for its nutritious oil-rich seeds; native to Asia
any of various leguminous plants grown for their edible seeds and pods	a source of oil; used for forage and soil improvement and as food
any of various seeds or fruits that are beans or resemble beans

bean (verb)	soya bean (verb)
hit on the head, especially with a pitched baseball