Go Off on a __, Suddenly Change the Subject
This page is the CodyCross answer for the clue below from Past and Present Tech, Group 1459, Puzzle 1 (Graphical User Interface).
Question is: Go Off on a __, Suddenly Change the Subject
and the answer is: TANGENT
Word Meaning:
TANGENT — (differential geometry) A straight line touching a curve at a single point without crossing it there.
Definitions from Wiktionary.