lichens
Refers to lichens as a group of organisms, often in biological or ecological contexts.
Lichens are a symbiotic association of fungi and algae.
Compound of 地衣 (chi'i, 'lichen') + 類 (rui, 'kind, group'). The term 地衣 itself is a Sino-Japanese word meaning 'ground clothing', referring to the appearance of lichens covering surfaces.