Air-Filled Ring Inside a Bicycle Wheel
This page is the CodyCross answer for the clue below from Professions, Group 1527, Puzzle 2 (Librarians).
Question is: Air-Filled Ring Inside a Bicycle Wheel
and the answer is: INNERTUBE
Word Meaning:
INNER TUBE — An inflatable rubber tube with a valve inserted into the casing of a pneumatic tyre.
Definitions from Wiktionary.