dwell on/upon something phrasal verb (
see also dwell)
to think or talk for too long about something, especially something unpleasant:
That is not a subject I want to dwell on. [TahlilGaran] Dictionary of Contemporary English ▲
dwell upon{v.} To stay on a subject; not leave something or want to leave; not stop talking or writing about.
Joe dwelt on his mistake long after the test was over. Our eyes dwelled on the beautiful sunset. The principal dwelled on traffic safety in his talk. Compare: HARP ON. Contrast: TOUCH ON.
[TahlilGaran] English Idioms Dictionary ▲