Worm

A computer program that can run independently, can propagate a complete working version of itself onto other hosts on a network and may consume computer resources destructively. 

See NIST SP 800-82 Rev. 2 under Worm RFC 4949 for more information. 

A self-replicating program that propagates itself through a network onto other computer systems without requiring a host program or any user intervention to replicate. 

See NIST SP 800-28 Version 2 under Worm for more information. 
 
A computer program or algorithm that replicates itself over a computer network and usually performs malicious actions. 

See NIST SP 800-47 under Worm for more information.
 
Write-Once Read Many.  

See NIST SP 800-88 Rev. 1 under WORM for more information. 

A self-replicating, self-propagating, self-contained program that uses networking mechanisms to spread itself.  

See NIST SP 800-12 Rev. 1 under Worm for more information.