Related Clues:

• Action to a newborn baby's bottom
• Affix carelessly, with 'on'
• Reaction to an offensive line, perhaps
• Give a high-five to
• Insult, so to speak
• Hit Stooge-style
• A blow between pals
• Sound of a heavy blow
• Hit with open hand
• A blow among pals
• What a blow it is when your friends come back!
• That's the way to knock up your friends
• Your 30 across's return is a bit of a blow
• That's enough to knock your friend back
• That's enough to knock your friends back