Sump = below grade pit or tank that holds drained water.
If it’s a residential thing it redistributes pooled water. It looks like a french drain and has a grate. The water goes down their and either uses gravity or percolates the water away into an alternate collection area. It can be installed to fix crawlspace rot.
In commercial applications a sump pump redistributes working water used in the manufacturing process for re-circulation and filtration.
