Glossary Aviation TermsAll | # A B C D E F G H I J K L M N O P Q R S T U V W X Y Z There are currently 2 terms in this directory beginning with the letter E.ECCMElectronic counter-countermeasures, a mechanism to overcome ECM.ECM Electronic countermeasures, generally meaning “jamming” or creation of electronic noise to break a hostile sensor lock.