The words gambol, gamble sound the same but have different meanings and spellings. Why do gambol, gamble sound the same even though they are completely different words?
The answer is simple: gambol, gamble are homophones of the English language.
To expose to hazard; risk: gambled their lives in a dangerous rescue mission.
To bet on an uncertain outcome, as of a contest.
To play a game of chance for stakes.
To take a risk in the hope of gaining an advantage or a benefit.
To leap about playfully; frolic.
A playful skipping or frolicking about.
Definitions from The American Heritage® Dictionary of the English Language, 4th Edition and Wordnik.
Homophones (literally "same sound") are usually defined as words that share the same pronunciation, regardless of how they are spelled.