Having a chain of more that about twelve carbon atoms.(adjective)
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Use "long-chain" in a sentence
"ALA, with eighteen carbons, is sometimes called a medium-chain omega-3; EPA and DHA are sometimes called long-chain omega-3 fats because EPA contains twenty carbons and DHA contains twenty-two."
"EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are the “long-chain” forms found in fish and fish oil."
"By contrast, most common vegetable or seed oils are comprised of long chain fatty acids LCFAs, also known as long-chain triglycerides or LCTs."