yam

yam

yam, common name for some members of the Dioscoreaceae, a family of tropical and subtropical climbing herbs or shrubs with starchy rhizomes often cultivated for food. The largest genus, Dioscorea, is commercially important in East Asia and in tropical America. The thick rhizomes, often weighing 30 lb (13.6 kg) or more, are used for human consumption and for feeding livestock. A number of species of Dioscorea are cultivated for extraction of diosgenin, a female hormone precursor used in the manufacture of the contraceptive pill. In the United States, cultivation of yams for food is restricted to the South, but the wild yam (sometimes used medicinally) is indigenous farther north, and another species, the cinnamon vine, is cultivated as a decorative plant. The sweet potato, which belongs to the morning glory family, is sometimes erroneously called yam. The S African elephant's-foot (Testudinaria elephantipes), also called Hottentot bread and tortoise plant, is sometimes grown in greenhouses; its large rootstock was formerly eaten by the natives. Yams are classified in the division Magnoliophyta, class Liliopsida, order Liliales, family Dioscoreaceae.

The Columbia Electronic Encyclopedia™ Copyright © 2022, Columbia University Press. Licensed from Columbia University Press. All rights reserved.

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Yam

 

any one of more than 30 plant species of the genus Dioscorea of the family Dioscoreaceae. Yams are cultivated for their tubers in the tropics and subtropics. The tubers are different morphologically (thickening of the hypocotyl, internodes, or rhizomes). In some species, they reach a length of 1.5 m and a weight of 50 kg. The tubers are used as food in a way similar to potatoes. The poisonous substances found in the tubers of some species are usually destroyed during boiling or baking. The most important species are the Chinese yam (D. batatas), winged yam (D. alata), D. esculenta, and the air potato (D. bulbifera).

REFERENCES

Ipat’ev, A. N. Ovoshchnye rasteniia zemnogo shara. Minsk, 1966.
Siniagin, I. I. Tropicheskoe zemledelie. Moscow, 1968.
Uphof, J. C. T. Dictionary of Economic Plants, 2nd ed. Lehre, 1968.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

What does it mean when you dream about a yam?

Yams are usually associated with the holiday season. The dreamer’s associations with this symbol may be rooted in memories of family celebrations. As a plant that grows under the ground, the yam is also a natural symbol of something deeply rooted in the unconscious mind.

The Dream Encyclopedia, Second Edition © 2009 Visible Ink Press®. All rights reserved.

yam

[yam]

(botany)

A plant of the genus Dioscorea grown for its edible fleshy root.

An erroneous name for the Puerto Rico variety of sweet potato; the edible, starchy tuberous root of the plant.

McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

yam

1. any of various twining plants of the genus Dioscorea, of tropical and subtropical regions, cultivated for their edible tubers: family Dioscoreaceae

2. Southern US any of certain large varieties of sweet potato

3. a former Scot name for the (common) potato

Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005