English

Noun

apple-pie order

1. (colloquial, dated) A neat and tidy arrangement or organization.
   • 1899, Joseph Conrad, Heart of Darkness, section 1

     And he was devoted to his books, which were in apple-pie order.

   • 1904, M.R. James, Oh, Whistle, and I'll Come to You, My Lad

     He was made welcome...and was able before retiring to rest to arrange his materials for work in apple-pie order upon a commodious table which occupied the outer end of the room...

References

• Partridge, Dictionary of Slang, 7th Ed.
• "Apple-pie order" in Michael Quinion, Ballyhoo, Buckaroo, and Spuds, 2004.