Tawdry means cheap, shoddy, or tasteless. It can be used to describe almost anything from clothes to people to even events or affairs.
You know that shiny black slip you picked up for nothing at a garage sale and used as the skirt of your lion-tamer Halloween costume? It's a bit tawdry. But it would really be tawdry if you wore it on a regular day out. Tawdry things often have a hint of desperation and immorality — like tawdry extramarital affairs or tawdry tales. With tawdry decorations and jewelry, quality has been exchanged for lots of flash and shine.