The words pistil, pistol sound the same but have different meanings and spellings. Why do pistil, pistol sound the same even though they are completely different words?
The answer is simple: pistil, pistol are homophones of the English language.
The female, ovule-bearing organ of a flower, including the stigma, style, and ovary.
A firearm designed to be held and fired with one hand.
To shoot with such a handgun.
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.
If they are spelled the same then they are also homographs (and homonyms); if they are spelled differently then they are also heterographs (literally "different writing").