Electronic countermeasures and Electronic warfare

Electronic countermeasures noun - Electronic warfare undertaken to prevent or reduce an enemy's effective use of the electromagnetic spectrum.

Electronic warfare and electronic countermeasures are semantically related. In some cases you can use "Electronic warfare" instead a noun phrase "Electronic countermeasures".

Electronic warfare noun - Military action involving the use of electromagnetic energy to determine or exploit or reduce or prevent hostile use of the electromagnetic spectrum.

Electronic countermeasures and electronic warfare are semantically related. Sometimes you can replace phrase "Electronic countermeasures" with "Electronic warfare", this phrases are similar.