These two words are the common words for people from Asia, particularly Cambodia and Vietnam. They mean similarly almost the same but refer to different things. In the straight meaning, temple is explained as a building devoted to worship of god while pagoda means a Hindu or Buddhist temple, typically in the form of many tier temple. In a clear context of Cambodia, temples are pretty much referred to any worshipped places for ancestors, gods and kings but is more likely addressed as heritage buildings; for example, Angkor Wat Temple or Bayon Temple.
Meanwhile, pagoda simply refers a place where the Buddhist monks stay or live in and also where people can pray for their ancestors. You can also find it almost anywhere throughout the country. Ounalorm and Monhamoney Pagodas are ones of the popular pagodas based in capital of Phnom Penh.
In contrast, since I came to Australia, I was so surprised how people address pagoda as temple. It’s hard for me to clearly distinguish between these two word as it’s used differently. Unlike Asia, there are more churches than temple or pagoda. Asian temples in Australia are pretty much praying and community places for each culture, but not in the way I would address as heritage buildings like Angkor Wat at all. In my opinion, I am not sure if other Asian temples in Australia calling praying building as temple, but whenever you are talking to Australians, either born or raised in Australia, they understand temple as pagoda. I have also tried surfing Internet, the term ‘Temple’ is common in Australia, in opposition to Cambodia, where the term ‘Pagoda’ is popular. In that sense, WHEN YOU ARE IN AUSTRALIA, DO AS THE AUSTRALIANS DO, and WHEN YOU ARE IN CAMBODIA, JUST DO AS CAMBODIANS DO. By doing that, you won’t get wrong!