T-junction vs road junction

T-junction

noun
  • A similarly shaped section in a pipe, etc. 

  • An intersection of routes where one road terminates as it joins a (usually higher priority) road at approximately 90°. In most countries, a give way or stop road sign will be seen at a T-junction. 

road junction

How often have the words T-junction and road junction occurred in a corpus of books? (source: Google Ngram Viewer )