It’s good to expand our horizons and learn random facts.
Scruple. A feeling of doubt or uneasiness, a pricking of conscience.
This is derived from the Latin “scrupulous,” meaning a small stone or pebble. When Roman soldiers were on their long marches, sometimes small pebbles would become lodged inside their sandals, causing discomfort or unease. Our word “scruple” comes from this same awareness of something bothersome.
(Information provided by “The Complete Footwear Dictionary: Second Edition” by Dr. William A. Rossi, 2000.)