Succulent Plant
All the plants above are succulents. Source:

A succulent plant or simply “succulent” is a plant has some parts, usually stems or leaves, that are more than normally thickened and fleshy, usually in order to retain water in arid climates. The word “succulent” comes from the Latin word sucus, meaning juice or sap. Most Cactaceae (cactus), Crassulaceae (crassulas and sedums), Agavaceae (agaves) and Aizoaceae (living stones) are succulents, as are many Liliaceae, including aloes, gasterias and haworthias and Euphorbiaceae (euphorbias).