Literal:
* The baseball player hit the ball with a smack that echoed through the stadium.
* The door closed with a smack, startling the cat.
* She smacked her lips in anticipation of the delicious meal.
Figurative:
* The news about the scandal hit her like a smack in the face.
* The restaurant was right in the smack of downtown.
* The old man smacked his forehead in frustration.
Informal/Slang:
* He smacked his gum loudly, which annoyed the other passengers.
* You really got smacked in that game!
* "Hey, you got any smokes?" "Yeah, smack one out of the pack for me."
Note: "Smack" can also be used in a vulgar way, particularly when referring to drugs. Be careful when using this word and consider your audience.