CMO
- CAMPUS Magazine Online
- CMOS (disambiguation)
- Canadian Mathematical Olympiad
- Central massive object
- Cetyl myristoleate
- Check Mii Out
- Chi Mei Optoelectronics
- Chicago, St. Paul, Minneapolis and Omaha Railway
- Chief marketing officer
- Chief medical officer
- Chief merchandising officer
- Chinese Mathematical Olympiad
- Citizens' Municipal Organisation
- Civil-military operations
- Collateralized mortgage obligation
- Collective rights management
- Commodore's Messenger Organization
- Congressional caucus
- Contract manufacturing organization
- Corticosterone 18-monooxygenase
- Cubic mile of oil
- Cyprus Mathematical Society