barrel cactus

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Any of several cacti, especially in the genera Ferocactus and Echinocactus, having unbranched, globular to columnar, ribbed spiny stems.

Century Dictionary and Cyclopedia

1. n. The bisnaga, Echinocactus: so named from its form and size. See Echinocactus and visnaga.

Wiktionary

1. n. Any cactus with an approximately barrel-like shape.

GNU Webster's 1913

1. n. any of several large cacti native to the southwestern U. S. and Mexico, having a short cylindrical form with deep vertical ribs and bearing sharp spines. They are classed in the genera Ferocactus and Echinocactus.

WordNet 3.0

1. n. a cactus of the genus Ferocactus: unbranched barrel-shaped cactus having deep ribs with numerous spines and usually large funnel-shaped flowers followed by dry fruits
2. n. any cactus of the genus Echinocactus; strongly ribbed and very spiny; southwestern United States to Brazil