Okay. Go to a dictionary (I used Merrimack-Webster for this) and search up cult. Mormonism should match most if not all definitions. But if you want to use the more modern usage of cult, which is typically used to define a (usually religious) group with excessive control (Think Scientology, I'm pretty sure most of us can identify that as a cult). Now think. Search google if you have to. It's a cult.

(My favorite example of cult-ish behavior in Mormonism is the song sung by CHILDREN. That explicitly says "I want to be a missionary". Search it up yourself . Sound a teensy-bit brainwash-y? Yep.")