A tidbit is a small amount of something delicious. You might have a tidbit to tide you over between lunch and dinner.
If you're tempted to feed your dog tidbits of your dinner, remember that that's a good way to turn him into a chubby dog that begs for food. The word tidbit can also mean "a bit of gossipy information," and you may notice yourself lingering where you can overhear a phone conversation, hoping for a few tidbits. Tidbit, or titbit in the U.K., comes from the dialectical tid, "fond or tender."