What does chloroform mean?
Chloroform is a colorless, sweet-smelling liquid with the chemical formula CHCl₃, known formally as trichloromethane. First synthesized in the early nineteenth century, it achieved fame as one of the first effective general anesthetics, transforming surgery in the mid-1800s by allowing doctors to operate on unconscious patients. Its medical use declined after it was found to pose serious risks, including fatal cardiac arrhythmia and liver damage, and safer agents such as ether derivatives took its place. Today chloroform survives mainly as an industrial solvent and laboratory reagent, though its production and sale are regulated because it can be toxic and potentially carcinogenic. In popular culture, chloroform endures as a dramatic shorthand for sudden unconsciousness, despite being far slower-acting than fiction suggests. Both noun and verb senses exist: the verb means to render someone insensible with the substance.
A colorless, volatile, sweet-smelling liquid compound (CHCl₃) formerly used as a general anesthetic and now used chiefly as an industrial solvent and chemical reagent.
"The chemist handled the chloroform inside a fume hood."
Uncountable; no standard plural in ordinary use.
To render (someone) unconscious or insensible by administering chloroform.
"He claimed the victim had been chloroformed before the attack."
Chiefly literary or journalistic.
'Chloroform' is an uncountable mass noun; it does not take a plural in ordinary usage. Quantities are expressed with measures such as 'bottles of chloroform'.
"The lab stored several bottles of chloroform under lock."
Chloroform helped birth modern surgery by putting patients to sleep — but it was never actually the 'knock-out in one rag' drug that countless crime dramas make it out to be.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of chloroform
Chloroform was named in the early nineteenth century from French 'chlore' (chlorine) plus 'forme', referring to formic acid, reflecting early beliefs about its composition; both elements trace back through Latin and Greek ('chlōros', pale green, from Greek; formic from Latin 'formica', ant). It was first synthesized around 1831 independently by several chemists, including Samuel Guthrie in America and Eugène Soubeiran in France, and introduced as an anesthetic by James Young Simpson in 1847. Related words sharing these roots include chlorine, chloride, and formaldehyde.
Related word forms
How chloroform is actually used
As a noun, 'chloroform' is uncountable. The verb form is chiefly literary or journalistic; real-world criminal use of chloroform to quickly incapacitate victims is largely a fiction trope, since it typically takes several minutes of continuous inhalation to cause unconsciousness. In chemistry contexts, the systematic name 'trichloromethane' may be preferred.
Easily confused with chloroform
Formaldehyde is a different chemical (HCHO) used in embalming and preservation, whereas chloroform is CHCl₃, historically an anesthetic.