1. To press together and open the lips quickly and noisily, as when eating or tasting: "You could hear the cook smack his lips as he tasted the food he was preparing for dinner."
2. To strike sharply and with a loud noise; such as, a blow delivered with an open hand: "She smacked her hand on top of the table to emphasize a major point in her speech."
3. A hard slap or hit; including a loud noise that is made when something hits anything else in a forceful way: "We could hear the big book fall to the floor with a smack."

A hard slap or hit; including a loud noise that is made when something hits anything else in a forceful way: "We could hear the big book fall to the floor with a smack."

1. A loose coatlike outer garment, often worn to protect the clothes while working: "She wore an artist's smock whenever she was painting her pictures."
2. A woman's loose blouse-like garment, reaching below the waist and worn over slacks, etc.: "We see more and more girls each of whom is wearing a smock when they are in school or even walking around town."