Electropedia is an online vocabulary with more than 20000 definitions.
It is produced by IEC.
The International Electrotechnical Commission (IEC) is the world’s leading organization that prepares and publishes International Standards for all electrical, electronic and related technologies.
One can give the search term in english or french, and the result is given in several languages: Arabic, Chinese, German, Italian, Japanese, Portuguese, Polish, Russian, Spanish and Swedish (coverage varies by subject area).
For example, for term “gateway”, it gives:
functional unit that connects two computer networks with different network architectures and protocols
NOTE 1 – The computer networks may be local area networks, wide area networks, or other types of networks.
NOTE 2 – Examples of gateways are a LAN gateway, a mail gateway.
For full example, see link for “gateway” definition.