A chock is a heavy-duty marine fitting or fixture, usually made from some type of robust metal such as brass or steel. It is typically found on the deck of a boat or ship, designed with a guide or passage specifically intended to lead or run anchor or mooring lines through it. This provides secure and reliable anchorage or moorage, preventing any potential damage to the vessel's hull by preventing the lines from rubbing directly against it. They offer control and directionality to the lines and significantly help in minimizing stress, chafing, or wear on the lines even under severe sea conditions or heavy loads.

1. The vessel had strong, metal chocks, to keep the mooring lines secure during harsh weather conditions. 2. The sailor moved confidently, threading the heavy anchor lines through the deck chocks before securing them tightly. 3. To ensure a safe anchorage at the busy marina, the boat was equipped with stainless steel chocks that were rust and corrosion resistant. 4. Rigorous inspections were carried out on the ship's chocks, ensuring they were not damaged and were adequate for the heavy weight of the anchor lines. 5. While shopping for boat equipment, I made sure to get high-quality brass chocks to assist in making my vessel mooring process easier and more effective.

The term "chock" is commonly associated with a wooden or metal support that stabilizes a boat or ship, but in a nautical context, chocks are also fittings on a ship's deck through which anchor or mooring lines are led. The word originated from the Old French word "choque" which means "a block". Interestingly, in the past, sailors used to vigorously polish these chocks regularly to prevent the ship's lines from being damaged. This frequent polishing is thought to have given rise to the term "chock-a-block," meaning something that is tightly packed or completely filled, reflecting how these chocks often appeared on the crowded decks of ships.