noun
BiologyWith plural agreement: animals of the largest size category; especially benthic or soil animals which are at least several centimetres in length, such as vertebrates and large invertebrates; specifically those of a particular habitat, region, etc. Also (with singular agreement): a group, class, community, or list of such animals.
Origin
Early 20th century. From macro- + fauna.
Are You Learning English? Here Are Our Top English Tips