Computer Security Incident Response Team (CSIR) definition in Computer Security terms:
Definition(s): A capability set up for the purpose of assisting in responding to computer security-related incidents; also called a Computer Incident Response Team (CIRT) or a CIRC (Computer Incident Response Center, Computer Incident Response Capability).
Source(s): NIST SP 800-61 Rev. 2
reference: CSRC Glossary