"Topic areas" refers to specific subjects or areas of discussion or study. It could be a particular theme or category within a larger topic. Full definition
We have put together eight sets of images in topic areas: renewable energy, climate change, transport, costume, recycling, plants, farming, water and sanitation. (tes.com)
GCSE PE 6 mark question frameworks for a range of topic areas. (tes.com)
Other topic areas include studying materials that form in temperatures above 2000 °C, using quantum physics to create better computers, and studying how microbial communities may help host organisms respond to stress. (sciencemag.org)