Flame __, Substance That Slows the Spread of Fire
This page is the CodyCross answer for the clue below from Water Park, Group 750, Puzzle 2 (Aquatic Playground).
Question is: Flame __, Substance That Slows the Spread of Fire
and the answer is: RETARDANT
Word Meaning:
RETARDANT — (often in combination) Serving to impede (slow down) the action of something
Definitions from Wiktionary.