The words pairing, paring sound the same but have different meanings and spellings. Why do pairing, paring sound the same even though they are completely different words?
The answer is simple: pairing, paring are homophones of the English language.
The combination or union of two things.
Present participle of pair.
Something, such as a skin or peel, that has been pared off.
The act of removing the outer covering or skin.
Definitions from Wiktionary, Creative Commons Attribution/Share-Alike License, 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").