Defer means to put off or delay. You can try to defer the inevitable by pushing “snooze” and falling back asleep, but eventually you're going to have to get up.
If you're excellent at pushing things to a later date and a master at procrastination, then you already know how to defer. But defer can also mean to comply with another person’s opinion or wishes. So when your boss finds out you deferred your work to shop online instead, you should probably defer when she asks you to come in and finish everything up over the weekend.