Adware
Software that pushes ads. Sometimes you agreed. Sometimes the installer lied. Either way it is extra code on the box.
Adware displays advertisements. It can ship as a disclosed extra in another product, or land without a meaningful yes. At the hostile end it is a delivery truck for more malware (see malvertising).
Strip unknown toolbars, lock down local admin, and stop fetching utilities from the first search-ad. Ad blockers help the human; they are not a corporate control plane.
Fact source: ASD's ACSC glossary.