From ActuallyAutistic Wiki
Infodumping refers to Autistic communication where an Autistic shares a bunch of information about a topic, often a special interest, all at once with another person or people. The Autistic infodumping may be more enthusiastic than earlier in the conversation before the infodumping, have a louder voice while sharing, speak faster and faster as they go on, and be so happy at sharing the information that they don't realize when the audience has lost interest in the topic. An example for me is that I can talk about Anakin Skywalker's life and psychology for hours and have definitely infodumped about him to people if Star Wars even remotely comes up in a conversation. Infodumping is also a form of love language.