To Have the Opposite Effect of What Was Intended
This page is the CodyCross answer for the clue below from La Bella Roma, Group 418, Puzzle 4 (Flavian Amphitheater).
Question is: To Have the Opposite Effect of What Was Intended
and the answer is: BACKFIRE
Word Meaning:
BACKFIRE — A premature explosion in the cylinder of a gas or oil engine during the exhaust or the compression stroke, tending to drive the piston in the wrong direction.
Definitions from Wiktionary.