electronic countermeasures electronic counter-countermeasures • electronic data processing · · · Info · Definitions · Synonyms · Characters · · electronic countermeasures · · Text Common · · Latin · · Scripts 26 · · Length 9 · · Syllables Definitions · · · (noun) electronic warfare undertaken to prevent or reduce an enemy's effective use of the electromagnetic spectrum. Synonyms: electronic countermeasures, ECM. · · Noun Definition 1 Synonyms · · · ecm · · Synonym 1 Characters · · space U+0020 a latin small letter a U+0061 c latin small letter c U+0063 e latin small letter e U+0065 i latin small letter i U+0069 l latin small letter l U+006C m latin small letter m U+006D n latin small letter n U+006E o latin small letter o U+006F 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