Generally it kind of retains the features of the pronunciation of the language it was borrowed from. In this case Greek, which generally pronounces every vowel in a word. Similar to Aphrodite (which one would expect to be pronounced Afro-dight).

I know that doesn't help much unless you have already built a guide in your head about how words of a certain language are pronounced and can guess what language that word originates from. You might need to consult a dictionary to find out what language it was borrowed from, at which point you'll also see the pronunciation.