Residual Risk definition in Computer Security terms:
The potential for the occurrence of an adverse event after adjusting for the impact of all in-place safeguards. (See Total Risk, Acceptable Risk, and Minimum Level of Protection.).
Source(s): NIST SP 800-16
The remaining, potential risk after all IT security measures are applied. There is a residual risk associated with each threat.
Source(s): NIST SP 800-33
reference: CSRC Glossary