multiplug vs trip cord

multiplug

noun
  • An electric device that allows more than one plug to connect to a single socket by containing multiple similar sockets; particularly for mains electricity. 

trip cord

noun
  • A cord, line, lanyard, or wire that, when pulled, mechanically activates a device. 

  • A type of electrical extension cord: see pad. 

How often have the words multiplug and trip cord occurred in a corpus of books? (source: Google Ngram Viewer )