topic noun
ADJ. chosen, selected | broad, general, large, wide Before dealing with specific cases, she spoke on the broad topic of ‘discipline’. | diverse, wide-ranging The book covers such diverse topics as snorkelling and first aid. | narrow | central, dominant, important, key, main, major, principal | complex, difficult | conversational, essay, lecture, research | controversial, sensitive It might be better to avoid such a controversial topic. | historical, philosophical, scientific, social, etc.
VERB + TOPIC consider, cover, discuss, explore, deal with, focus on, look at, speak on, write on In the next chapter the writer focuses on the topic of adoption.
TOPIC + NOUN area, heading | work Our teaching is based largely on topic work.
PREP. on a/the ~ Mr Graham will speak on the topic of dog breeding.
PHRASES a choice of topic She was an excellent speaker, but I found her choice of topic strange. | a range/variety of topics, a topic of conversation/discussion His main topic of conversation is football.
You can also check other dicts: topic (English, 中文解释 ), wordnet sense, Collins Definition