the.com/topic

The thing you swore you wouldn't talk about, then did for an hour.

means The subject under discussion — what a conversation, essay, or argument is actually about.

from From Greek 'topika' meaning 'matters concerning places,' tied to 'topos' (place). Aristotle used it as the title of his work on commonplace arguments — rhetorical 'places' you could mentally go to find standard lines of reasoning. The sense drifted from 'a place to find an argument' to simply 'the subject itself.'

greek root
topos means place, as in location of argument
aristotle used it
wrote a book literally called Topics
conversation starter
also conversation ender, depending on delivery
sentence structure
usually comes first, often overstays welcome
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