Succulent are plants with leaves that are thickened, fleshy, or engorged, usually to retain water in arid climates or soil conditions. They are drought resistant due to this water retention in their leaves, stems, or roots, so often do not need a lot of water. The word succulent comes from the Latin word sucus, meaning 'juice', or 'sap'. The most popular succulent is the cactus! All cacti are succulents, but not all succulents are cacti.