Real Dictionary

sweet potato
variable noun: Sweet potatoes are vegetables that look like large ordinary potatoes but taste sweet. They have pinkish-brown skins and yellow flesh.

sweet potato in American English
a tropical, trailing plant (Ipomoea batatas) of the morning-glory family, with purplish flowers and a fleshy, brownish, tuberlike root used as a vegetable
noun: a plant, Ipomoea batatas, of the morning glory family, grown for its sweet, edible, tuberous roots

sweet potato in British English
noun: a convolvulaceous twining plant, Ipomoea batatas, of tropical America, cultivated in the tropics for its edible fleshy yellow root