The Highest Ledge of a Bookcase
This page is the CodyCross answer for the clue below from Physics, Group 1900, Puzzle 1 (North and South Poles).
Question is: The Highest Ledge of a Bookcase
and the answer is: TOPSHELF
Word Meaning:
TOP SHELF — (US, idiomatic) Best, or high quality.
Definitions from Wiktionary.