ˈwälə̇sə̇z-, ˈwȯlisə̇z- noun
also wallace line
Usage: usually capitalized W
Etymology: after Alfred Russel Wallace died 1913 English naturalist
: a hypothetical boundary separating the characteristic Asiatic fauna and flora from that of Australasia, marking the common boundary of the Oriental and Australian biogeographic regions, and usually passing between Bali and Lombok, between Celebes and Borneo or to the east of Celebes, and to the east of the Philippines — see weber's line