Coverage definition in Computer Security terms:
Definition(s): An attribute associated with an assessment method that addresses the scope or breadth of the assessment objects included in the assessment (e.g., types of objects to be assessed and the number of objects to be assessed by type). The values for the coverage attribute, hierarchically from less coverage to more coverage, are basic, focused, and comprehensive.
Source(s): CNSSI 4009-2015 (NIST SP 800-53A Rev. 1, NIST SP 800-137)
NIST SP 800-137 (NISTIR 7298)
NIST SP 800-53A Rev. 4
reference: CSRC Glossary