Real Dictionary

taiga
variable noun: Taiga is the coniferous forest located in the northern regions of the world. It is just south of the tundra.

taiga in American English
a type of transitional plant community that is located between the arctic tundra and the boreal coniferous forests, having scattered trees: often it is considered to include the N regions of the boreal forests
noun: the coniferous evergreen forests of subarctic lands, covering vast areas of northern North America and Eurasia

taiga in British English
noun: the coniferous forests extending across much of subarctic North America and Eurasia, bordered by tundra to the north and steppe to the south