The words prince, prints sound the same but have different meanings and spellings. Why do prince, prints sound the same even though they are completely different words?
The answer is simple: prince, prints are homophones of the English language.
A male member of a royal family other than the monarch, especially a son of the monarch.
A man who is a ruler of a principality.
A hereditary male ruler; a king.
A nobleman of varying status or rank.
Plural form of print.
shortening of fingerprints
posters (usually photographic prints) that are replicas of fine art
Third-person singular simple present indicative form of print.
Definitions from The American Heritage® Dictionary of the English Language, 4th Edition, from Wiktionary, Creative Commons Attribution/Share-Alike License 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").