- secular theology
- secular trend
- secular trend of cancer
- secular variable
- secular variation
- Secunda Giedi
- Secunda Hyadum
- secure attachment
- secure data provenance
- secured claims in bankruptcy
- secure docking device
- secure electronic transactions protocol
- secure electronic transactions protocol, SET protocol
- secure gateway
- secure hypertext transfer protocol
- secure hypertext transfer protocol, S-HTTP
- secure kernel
- secure liquid encapsulation
- secure multi party computation
- secure multi-party computation
- secure multipurpose internet mail extensions
- secure multipurpose internet mail extensions, S/MIME
- secure muti-party computation
- secure network coding
- secure operating system