land bridge

noun
1.
Geology. an actual or hypothetical strip of land, subject to submergence, that connects adjacent continental landmasses and serves as a route of dispersal for plants and animals:
a prehistoric land bridge between Asia and North America.
2.
a transcontinental rail route between countries, as those in Europe and the Far East, considered faster and less costly than all-sea routes.
Also, landbridge [land-brij] /ˈlændˌbrɪdʒ/ (Show IPA).
Origin
1895-1900
British Dictionary definitions for land bridge

land bridge

noun
1.
(in zoogeography) a connecting tract of land between two continents, enabling animals to pass from one continent to the other
Encyclopedia Article for land bridge

any of several isthmuses that have connected the Earth's major landmasses at various times, with the result that many species of plants and animals have extended their ranges to new areas. A land bridge that had a profound effect on the fauna of the New World extended from Siberia to Alaska during most of the Tertiary and Quaternary periods (beginning approximately 65 million years ago), with some interruptions. Across this strip of land passed a number of organisms of Old World origin, including Homo sapiens.

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