adjective, slum·mi·er, slum·mi·est.
Examples from the Web for slummy
The narrow streets of Westminster are curious and interesting, if occasionally just a trifle "slummy."Highways and Byways in London|Mrs. E. T. Cook.
We then drove to the gardens, which lie across the river, in quite a slummy part of the town.A Journal from Japan|Marie Carmichael Stopes
Don't you believe she has been led away into any slummy place, for the sake of politics or anything else.Sunrise|William Black