Reply To: Adjacent, vertical angles and Nemeth switch
Tung,
Thank you for the question.
Although it is inconvenient, "Adjacent angles", "Vertical angles", "Alternate interior angles", "Supplementary angles", and "Corresponding angles" are all nontechnical phrases/labels/headings.
[These phrases would be technical if they were involved in computation. In the example you included (Thank you for doing so!), the phrases/labels are not involved in computation and so are not technical. It would be rare for any of those phrases/labels to be involved in computation.]
–Kyle