ecm eclosion • ecmnesia · · · Info · Definitions · Synonyms · Characters · · ecm · · Text Latin · · Script 3 · · Length 1 · · 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 · · · electronic countermeasures · · Synonym 1 Characters · · c latin small letter c U+0063 e latin small letter e U+0065 m latin small letter m U+006D