definition of
topic

[1] #1 topic n. [subject, theme] the subject matter of a conversation or discussion; "he didn't want to discuss that subject"; "it was a very sensitive topic"; "his letters were always on the theme of love". wn

[2] #2 topic n. [subject, issue, matter] some situation or event that is thought about; "he kept drifting off the topic"; "he had been thinking about the subject for several years"; "it is a matter for the police". wn