| Acronym | Definition |
|---|
| CTO | Chief Technology Officer (corporate title) |
| CTO | Chief Technical Officer (corporate title) |
| CTO | Cut Off (call centers) |
| CTO | Check This Out (chat) |
| CTO | Caribbean Tourism Organization |
| CTO | Commonwealth Telecommunications Organisation (UK) |
| CTO | Cyprus Tourism Organisation |
| CTO | Cancelled to Order (cancellation postmark) |
| CTO | Community Treatment Order (psychiatric term for forced drugging outside hospital context) |
| CTO | Chronic Total Occlusion |
| CTO | Commercial Travel Office (Defense Finance and Accounting Service) |
| CTO | Compensatory Time Off |
| CTO | Connection Timed Out |
| CTO | Central Ticket Office |
| CTO | Combined Transport Operator |
| CTO | Configured To Order |
| CTO | Color Temperature Orange (photography) |
| CTO | Colorado Tourism Office |
| CTO | Central Telegraph Office |
| CTO | City Ticket Office |
| CTO | Cells Tissues Organs |
| CTO | Certificate to Operate (USAF system certification) |
| CTO | Certificate to Operate |
| CTO | Control Tower Operator |
| CTO | Centre for Terrestrial Ecology (Heteren, Gelderland, The Netherlands) |
| CTO | Cancel To Order (stamp collecting) |
| CTO | Contract Travel Office |
| CTO | Cervical-Thoracic Orthosis |
| CTO | Customized to Order |
| CTO | Certified Television Operator (Society of Broadcast Engineers) |
| CTO | Chief Telecommunications Officer |
| CTO | Cost Take Out |
| CTO | Clinical Technology Organisation |
| CTO | Container Terminal Operator |
| CTO | Chief Transport Officer |
| CTO | Communications Tasking Order (US Air Force) |
| CTO | Cadet Training Officer |
| CTO | Combined Test Organization (US Army) |
| CTO | Conventional Takeoff |
| CTO | Commercial Taxes Officer (India) |
| CTO | Commercial Transportation Office |
| CTO | Crack Tip Opening |
| CTO | Commander Task Unit |
| CTO | Central Texas Opportunities (USA) |
| CTO | Concurrent Test and Operations (Army) |
| CTO | Campus Teaching Observatory (University of Florida) |
| CTO | Corrections Training Officer (law enforcement) |
| CTO | Contract Tracking and Oversight |
| CTO | Cut-Through Operation |
| CTO | Counter-Terrorist Operative (gaming) |
| CTO | Controlled Transient Oscillation |
| CTO | Consejo Técnico Operativo |
| CTO | Cognizant Transportation Office |
| CTO | Certified Tradeable Offset |
| CTO | Campus Technology Operations (Sprint) |
| CTO | (USN Rating) Cryptologic Technician (Communications) |
| CTO | Cadet Third Officer |
| CTO | Control Technology Office |
| CTO | Consolidated Tasking Order |
| CTO | Continental Test Organization |
| CTO | Controller Training Outline |
| CTO | Change Task Order |
| CTO | Commander's Training Objective (US Army) |
| CTO | Clerical Training Officer |
| CTO | Confocal/TEM Overlay |
| ctO | Concentration of Total Oxygen (also seen as ctO2) |
| CTO | Contribution Towards Overhead |