security service security review • security staff · · · Info · Definitions · Characters · · security service · · Text Common · · Latin · · Scripts 16 · · Length 6 · · Syllables Definitions · · · (noun) the government agency in the United Kingdom that is responsible for internal security and counterintelligence on British territory. Synonyms: Security Service, MI, Military Intelligence Section 5. · · Noun Definition 1 Characters · · space U+0020 c latin small letter c U+0063 e latin small letter e U+0065 i latin small letter i U+0069 r latin small letter r U+0072 s latin small letter s U+0073 t latin small letter t U+0074 u latin small letter u U+0075 v latin small letter v U+0076 y latin small letter y U+0079