Time-Travel Event Where You're Your Own Grandpa
This page is the CodyCross answer for the clue below from Cats, Group 1723, Puzzle 5 (Marking Territory).
Question is: Time-Travel Event Where You're Your Own Grandpa
and the answer is: PARADOX
Word Meaning:
PARADOX — An apparently self-contradictory statement, which can only be true if it is false, and vice versa.
Definitions from Wiktionary.