Off on a Completely Different Line of Thought

This page is the CodyCross answer for the clue below from Treasure Island, Group 1037, Puzzle 4 (Thar She Blows).

Question is: Off on a Completely Different Line of Thought

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.

Off On A Completely Different Line Of Thought - Treasure Island CodyCross Answers | CodyCross Solutions