What counts as sexual assault? (Warning involves myself, a minor at the time, not currently a minor)

I feel unsure about whether or not my parent sexually assaulted me when I was 9/10 years old. Slept in same bed as me for months after my parents divorced. While I would be clothed, my dad would sleep naked. He would cuddle me and sometimes reach his arm under my shirt and put his hand over my breast area (though I didn’t have any, I hadn’t done through any kind of puberty). Sometimes in mornings I could feel an erection touching me, but it would be while he was asleep and never when he was awake. I felt weird about it at the time, never said anything to him. Eventually I felt weird enough to want to sleep in my own bed and I did, and nothing ever happened again, and I never spoke to him about it.

I’ve always felt weird about it but never felt like it was “real” sexual assault because I never actually was sexually abused I guess? Idk. I think about it pretty often and I’m now 30, he is dead. I guess I’m just looking for validation or clarification.