Ground meat is processed in a grinder ... it produces a fine mince (I think that in the UK ground meat is called minced meat - eh, YT?). Minced or ground - it's a fine mince. Chopped meat is, as the name implies, chopped and is generally not as fine textured as ground or minced. A cousin of chopped is "chipped" - which is more "flaked" than chopped or minced.
Back to the original question:
Originally Posted by justplainbill
Was there a time when hamburger meat was referred to as chopped meat?
What is hamburger meat? Hamburger (as labeled in the US meat markets/grocery stores) these days is generally analogous to "fatty ground scrap meat" (70/30) - but you can make a hamburger out of chipped, chopped, minced, or ground meat - and from different cuts like lean cuts of sirloin or fillet.