smacking (Noun) — The act of smacking something; a blow delivered with an open hand.
smacking (Verb) — Deliver a hard blow to. ex. "The teacher smacked the student who had misbehaved"
smacking (Verb) — Have an element suggestive (of something). ex. "his speeches smacked of racism"
smacking (Verb) — Have a distinctive or characteristic taste. ex. "This smacks of nutmeg"
smacking (Verb) — Kiss lightly.
smacking (Verb) — Press (the lips) together and open (the lips) noisily, as in eating.