The term 'prickly desert plant' can be summarized as a CACTUS, which is a six-letter word. Cacti are succulent plants that are native to the Americas and thrive in arid and semi-arid climates. They are characterized by their thick, fleshy stems and spines, which help them to conserve water in dry environments. Cacti have adapted to survive in extreme conditions, making them an iconic symbol of the desert.