ling ko vs water chestnut plant

ling ko and water chestnut plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
ling ko	Yes	No	No	No
water chestnut plant	Yes	No	No	No

As nouns, water chestnut plant is a hypernym of ling ko; that is, water chestnut plant is a word with a broader meaning than ling ko:

ling ko: water chestnut whose spiny fruit has two rather than 4 prongs
water chestnut plant: a plant of the genus Trapa bearing spiny four-pronged edible nutlike fruits

Other hypernyms of ling ko include caltrop, water chestnut.

ling ko (noun)	water chestnut plant (noun)
water chestnut whose spiny fruit has two rather than 4 prongs	a plant of the genus Trapa bearing spiny four-pronged edible nutlike fruits