Pronunciation: [klˈɪŋkə] (IPA) 
The word "clinker" is spelled with a "c" and an "l". The phonetic transcription of the word is /ˈklɪŋkər/. The "c" is pronounced as /k/, the "l" sounds like /l/, the "i" is pronounced as /ɪ/, the "n" as /ŋ/, the second "k" as /k/ and the "e" and "r" together form an "ər" with a schwa sound. This word refers to a hard, dark, fused mass of matter formed when coal or other materials are burned.
Clinker refers to a hard, dense, and usually dark-colored residue that is formed during the process of burning materials like coal and limestone in a kiln or furnace. This residue typically results from the high-temperature fusion of impurities and minerals present in the raw material, such as silica, alumina, and iron oxide. It is commonly found as a byproduct in industries like cement manufacturing, metallurgy, and coal combustion.
In the context of cement production, clinker specifically pertains to the nodules or pellets that are produced when raw materials, such as limestone and clay, are heated to extremely high temperatures in a kiln. These clinkers are subsequently finely ground and mixed with a small amount of gypsum to form cement. The clinker itself is composed primarily of calcium silicates and aluminates, which are responsible for the cement's binding and hardening properties.
Outside of cement production, clinker can also be used to describe irregularly shaped masses or lumps of solidified material that result from incomplete combustion or fusion of certain substances. For instance, clinkers can be found in coal fires or as residues in power plants that use coal as a fuel source. In a broader sense, clinker may refer to any solidified or fused residue that is formed as a result of high-temperature processes, although its most common and widely recognized usage is within the cement industry.
• In min., the black oxide of iron; the slaggy ferruginous crusts that form on the bars of engine-furnaces.
• Very hard bricks; bricks run together and glazed over by excessive heat; clinker-bar, in a steam-engine, the bar fixed across the top of the ash-pit; clink-stone, rock of a greyish-blue colour which rings with a metallic sound when struck.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.
The word "clinker" has a few different etymological origins depending on its specific usage. Here are a few of the main origins:
1. Clinker (noun referring to a stony residue):
- Old English Origin: The Old English word "clencan" means "to clench" or "to cling". In the context of clinker, it refers to the way the stony residue "clings" together after being burned.
- Medieval Dutch Origin: The Middle Dutch word "klinkaerd" means "a kind of brick". "Klinkaerd" later evolved into "klynker", and ultimately became "clinker" in English.
2. Clinker (noun referring to the sound):
- Onomatopoeic Origin: The word "clinker" may also have originated from the onomatopoeic qualities of the sound it represents.
