Axile placentation refers to the arrangement of ovules in a central axis of the ovary. It is a common type of placentation found in various plants. However, there are also other terms used to describe this type of placentation, including central placentation and placenta marginal. These synonyms refer to the same characteristic of the ovules being attached to the central axis of the ovary. Another term used to describe axile placentation is intruded parietal placentation, which indicates that the ovules are borne on the inner walls of the ovary, intruding towards the center. Overall, these synonyms are useful in understanding and communicating the structural morphology of plants.