What is a midden?

it’ll be like 7 more sources.
https://dc.statelibrary.sc.gov/bitstream/handle/10827/33799/Chicora_Research_Contributions_154_1994-09-27.pdf?sequence=1&isAllowed=y
https://scholarcommons.sc.edu/cgi/viewcontent.cgi?article=1011&context=archmonth_poster