dumb cane dumb·cane uncommon noun 1. a evergreen plant with large showy dark green leaves; contains a poison that swells the tongue and throat hence the name Synonymsdumb canemother-in-law plantmother-in-law's tongueDieffenbachia sequine Related words Broader terms arum Parts Dieffenbachia WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.
