Wow I just realized I kinda got behind somehow. So here is my C post.
The word cult is quite a misunderstood word, and it is used in a context to evoke fear and potential danger. However when used by polytheists the word cult has a different connotation. From the Latin cultus, a cult of a given deity is the prescribed worship that is given to said deity. Therefore if I am engaging in the cultus of Apollon, I am engaging in the proper methods and manner of worship given to him. A cult then is something more specific than the broader term of religion from the Latin religio. Religion is about the collective beliefs and actions in worship as a whole, whereas cult is typically specific to a singular or small group of deities. As such cultus can be regarded as subset to religio, rather than counter to religion as most modern understandings have it.
A cultus is also often location specific. In which case a deity can easily have differing cultus given to him depending at what temple he or she is worshiped even in the same given city. So, for instance (and bear with me, I know that the word is Latin rather than Hellenic but I am going to give Hellenic examples here because I feel that it is just as true in the Hellenic context), the cultus that one were to give Apollon Agyieus or Thrymbaeus before the household entrance would be different from the cultus given to him at the Pythian temple and that in turn would be different from cultus given to Apollon at the Daphne temple and so on. Romans and Hellenes were rather particular to having many temples to the same god that varied in function, and this function would often dictate how the cultus was given to the god in question.
So this is a bit of a short post for PBP but that is really all I have to say about the matter 🙂