Okay. What exactly is a spice? I wish I knew. I’ll have a go. In general I would say that they are dried parts of plants. This may mean leaves, roots, bark, fruits or pods - anything that grows - even the dried juices. Some plants provide herbs and spices from different parts of the plant, like coriander (US: cilantro). On the whole I would say that a spice is a dried part of a plant which flavours food. But you can shoot me down in flames if you like. I don't feel strongly.