Jambudeep (Jambudweep) is a key concept in Jain cosmology. It refers to the great southern continent, Jambudvipa, which surrounds Mount Meru in the Jain universe. Jambudeep is often mentioned as the land where much of human life and many Jain teachings and Tirthankaras' activities are described to have occurred. It is part of the symbolic map of the cosmos, not a modern geographic place. There are variations in how Digambaras and Śvetāmbaras describe certain details, but both traditions treat Jambudeep as an important sacred region within the Jain cosmology. For a concise, authentic Jain description, you can read more about Jambudweep Complex here