The words hold, holed sound the same but have different meanings and spellings. Why do hold, holed sound the same even though they are completely different words?
The answer is simple: hold, holed are homophones of the English language.
To have and keep in one's grasp: held the reins tightly.
To aim or direct; point: held a hose on the fire.
To keep from falling or moving; support: a nail too small to hold the mirror; hold the horse steady; papers that were held together with staples.
To sustain the pressure of: The old bridge can't hold much weight.
Simple past tense and past participle of hole.
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").