yam vs yam plant

yam and yam plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
yam	Yes	No	No	No
yam plant	Yes	No	No	No

As nouns, yam and yam plant are synonyms defined as:

yam and yam plant: any of a number of tropical vines of the genus Dioscorea many having edible tuberous roots

yam (noun)	yam plant (noun)
sweet potato with deep orange flesh that remains moist when baked	any of a number of tropical vines of the genus Dioscorea many having edible tuberous roots
edible tuberous root of various yam plants of the genus Dioscorea grown in the tropics world-wide for food
any of a number of tropical vines of the genus Dioscorea many having edible tuberous roots
edible tuber of any of several yams