1. (

• whack

) the sound made by a sharp swift blow ;

2. (

• knock ,
• belt ,
• rap ,
• whack ,
• whang

) the act of hitting vigorously; "he gave the table a whack" ;

1. (

• whack ,
• wham ,
• whop ,
• wallop

) hit hard; "The teacher whacked the boy" ;