A proper state of a place, meaning it’s messy, untidy, and looks like it’s been hit by a small tornado. Usually said with full parental disappointment, especially about a teenager’s bedroom. Comes from “the tip” meaning the rubbish dump, so if your room’s a tip, congratulations, it’s basically landfill with posters.
"Mum: Sort your room, it’s an absolute tip. Me: I know where everything is. Mum: Yeah, under the crusty plates and three weeks of socks, you grub"