Printed Circuit Boards glossary. (English). Other good resources in that area also.
OpenCourseware: MIT (Massachusetts Institute of Technology) course materials are available for free to anybody, "spanning MIT's entire curriculum": Architecture and Planning, Engineering, Health Sciences and Technology, Humanities, Arts, and Social Sciences, Management, Science, etc. (English)
Many practical resources (including a glossary and tutorials, step-by- step instructions) for making printed circuit boards (PCBs).
Downloadable Russian-English electronics glossary.
Svetlana Kyyashko found this downloadable electronics dictionary (2 MB): "Dictionary 2000 contains English, French, Polish, Russian, Latin, Swedish, Norwegian, Portuguese, Spanish, Italian. " The page is in Russian.
Rowan Morrell highly recommends this IEC International Electrotechnical Vocabulary for any electronics-related job, which "has a wide range of electrical terms listed in English, French and German."
Leo Lauria points out this amazing list of links to technical glossaries.
Michael Molin suggests the Wiley Encyclopedia of Electrical and
Electronics Engineering. You can search the names of articles for free.
Iain Mackenzie points out the German Conrad catalog, which contains
lots of useful information about electronic equipment.