The term 'OLLA' is a four-letter word that is used to describe a type of leaf used for writing paper. OLLA is a type of palm leaf that is commonly used in India and other parts of South Asia for writing paper. It is made from the leaves of the palmyra palm tree, which is native to India and Sri Lanka. The leaves are dried and then cut into thin strips, which are then woven together to form a sheet of paper. OLLA paper is known for its durability and is often used for religious texts and manuscripts.