Related Clues:

• Matchless
• Slipper part
• Boot bottom
• Cobbler's concern
• Seafood serving
• Flatfish
• Fish dish
• Lone fish?
• See 18-Across
• Possible splinter site
• Kind of proprietor
• It's underfoot!
• Cod's neighbor in the showcase
• ''O --- Mio''
• Cod's showcase neighbor, perhaps