The term 'Forest Northern' can be broken down into two crossword solutions: Taiga (5 letters) and Northern. Taiga is a type of biome, also known as boreal forest or snow forest, which is found in the northern hemisphere. It is characterized by coniferous trees such as pines, spruces, and larches, and is the largest terrestrial biome in the world. Northern refers to the direction of the taiga, which is located in the northern parts of the world.