Related Clues:

• Cleavage
• Alley "oops"
• Word with "stock" or "banana"
• Challenge in an alley
• Break apart
• Cut, cleft
• Cleave or divide
• Chop or divide
• Cleave or break up
• Divide, break apart
• O, forbid this from being in Argyll
• With 51-Across, nitpick ... or a hint to 17-, 37- and 60-Across
• Candlepins bummer
• See 9
• See 18