Infalling is a term that refers to the action of falling in, typically used in scientific contexts. There are several synonyms for infalling, including ingress, incoming, penetrating, infiltrating, and penetrating. These words refer to the act of entering or moving inward. Infalling is often used to describe the motion of matter or energy into a particular region or object. These synonyms can be used interchangeably according to the context. For example, "the infalling water created a pool underneath the waterfall" can be rephrased as "the incoming water created a pool underneath the waterfall." The use of these synonyms can add diversity to our writing and make it more descriptive.