Cilantro is the Spanish word for coriander, adopted into American English in the early 20th century to distinguish the fresh leaves and stems from the dried seeds (which Americans call coriander). This distinction is largely an American convention — British English uses "coriander" for both leaf and seed, as does most of the world. The Spanish cilantro is a variant of culantro, from Latin coriandrum, from Greek koriannon or koriandron. The Greek word may derive from koris ("bedbug"), because the smell of the unripe plant was compared to crushed bedbugs — an olfactory judgment that some modern noses share.
The love-it-or-hate-it nature of cilantro is one of the most studied phenomena in food perception genetics. A 2012 genome-wide association study by Nicholas Eriksson and colleagues identified the gene OR6A2, which encodes an olfactory receptor sensitive to certain aldehydes (particularly (E)-2-decenal) abundant in cilantro leaves. People with certain variants of this gene perceive these aldehydes as soapy, metallic, or unpleasant, rather than the fresh, citrusy flavor perceived by those without the variant. The prevalence varies by population: approximately 14% of people
Coriander/cilantro is one of the world's oldest culinary herbs. Seeds have been found in Neolithic archaeological sites, and the plant is mentioned in the Ebers Papyrus (c. 1550 BCE), one of the oldest medical texts in existence. It appears in the Bible (Exodus 16:31, where manna is compared to coriander seed) and was used by ancient Egyptians, Greeks, Romans, and Chinese. The herb is essential to Mexican, Thai, Indian, Portuguese, and Middle Eastern cuisines.
The American use of 'cilantro' reflects the influence of Mexican culinary vocabulary in the southwestern United States. As Mexican food culture expanded across the country, the Spanish term came with it. The dual naming — cilantro for leaves, coriander for seeds — is practical, as the two forms have dramatically different flavors and culinary applications. Other languages manage without this distinction, but the American lexical split has become firmly