a cactus, Schlumbergera truncata (or Zygocactus truncatus), native to Brazil, having stems with leaflike segments and showy red flowers and often cultivated as a houseplant.
Origin of crab cactus
An Americanism dating back to 1895–1900
Also called Thanksgiving cactus.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019