Squares in a sudoku, e.g.
Else clues• Baseball lineups, e.g.
• Diamond complements
• Diamond groups
• Ed's 11A crazy Anne's nine-piece sets (7)
• Groups of nine
• Muses et al.
• N.L. teams, e.g.
• Near-decades
• Nonets
• Sets of nine
• Supreme Court groupings
• Supreme Courts, e.g.
• The planets and others