dud
1. Something that does not work as intended, is ineffectual, or is defective. This car I bought yesterday is a complete dud. It's engine won't even start!
2. Someone who is disappointing or unsuccessful. He turned out to be a bit of a dud. He doesn't have any plans to get a job; he just wants to watch TV all day.
duds
Clothes. What do you think of my new duds? You need to brush your teeth and put on your duds right now, or else you'll be late for school.