Electronic device and Thermionic valve

Electronic device noun - A device that accomplishes its purpose electronically.

Thermionic valve and electronic device are semantically related. In some cases you can replace phrase "Thermionic valve" with "Electronic device", this phrases are similar.

Thermionic valve noun - Electronic device consisting of a system of electrodes arranged in an evacuated glass or metal envelope.

Electronic device and thermionic valve are semantically related. You can use "Electronic device" instead a noun phrase "Thermionic valve".