CTX is a three-letter abbreviation with multiple meanings:

Medical C-terminal telopeptide, a blood serum biomarker that can be measured to assess bone turnover Ceftriaxone, an antibiotic Cefotaxime, an antibiotic Cerebrotendineous xanthomatosis, a genetic disorder Charybdotoxin, a toxin found in scorpion venom Chemotherapy, treatment of cancer with cytotoxic drugs Cholera toxin, a toxin responsible for the harmful effects of cholera Ciguatoxin, a neurotoxin produced by marine dinoflagellates Conotoxin, a toxin found in cone snail venom Crotoxin, toxic compound in snake venom Cyclophosphamide, an anticancer drug

Technology Centrex, a telephone service Citrix Systems, company best known for desktop virtualization software Chuntex Electronic, computer display manufacturer based in Taiwan CTX (camera), on the Mars Reconnaissance Orbiter CTX (computer virus) CTX (explosive-detection device) Collisionless Terrella Experiment, a levitated dipole at Columbia University

Business Caltex, where CTX is the stock symbol for Caltex Australia Limited Critical to X, key factors that are essential for the successful completion of a project or process.

Others Archaeological context Concordia University Texas, where 'C' is for Concordia and 'TX' is for Texas Countdown to Extinction, a thrill ride at Disney's Animal Kingdom, now known as DINOSAUR CTX, IATA airport code for the city of Cortland, New York, U.S.A.