intransitive verb
Definition: To produce small, hard pieces that form during the burning process, often in relation to coal or other materials.
Example: The furnace began to clinker as the temperature rose too high.
noun
Definition: A type of brick that has been burned to a very hard state, often used in construction, or a mistake or blunder in informal contexts.
Example: The builder used clinker bricks for the new wall because of their durability.