Something dilatory creates a delay. Remember when your math teacher asked you to work out a problem on the board and you tried to get her talking about her favorite theorems instead? That was a dilatory tactic.
The adjective dilatory comes from the Latin root word dilator, a noun that means "someone who puts off things" or "a procrastinator." If you are always late to appointments, people may accuse you of being dilatory, especially if they think you don't have a good excuse.