Sandalwood is a pleasant-smelling wood from a tree that grows in southern Asia, and also the sweet, thick oil taken from that wood. People carve it, burn it for the smell in temples, and put the oil in perfume and soap. In Taiwan you already know the smell from 拜拜: it is 檀香. The English name is simply sandal plus wood. That first half is an old name for this wood, which travelled from Sanskrit through Persian, Arabic, Greek, and Latin before it met English wood. It has nothing to do with the sandal you wear on your foot — that is a different word that only looks the same. Though actually, some film writing also uses Sandalwood, with a capital S, as a nickname for one of India's film worlds, the way people say Bollywood; that nickname came from this wood as a local product. The home meaning in a learner dictionary is still the wood and the oil.