Leaf veins are an important part of a plant's anatomy. They are the network of tubes that transport water and nutrients throughout the leaf. The term 'leaf vein' can be broken down into two parts: RIB and midrib. RIB is a three-letter word that refers to the smaller veins that branch off from the midrib. Midrib is a six-letter word that refers to the main vein running through the center of the leaf. Together, RIB and midrib form the leaf vein, which is essential for the health of the plant.