The words ait, ate, eight sound the same but have different meanings and spellings. Why do ait, ate, eight sound the same even though they are completely different words?
The answer is simple: ait, ate, eight are homophones of the English language.
Chiefly British A small island.
Past tense of eat.
The cardinal number equal to 7 + 1.
The eighth in a set or sequence.
Something having eight parts, units, or members, especially:
Sports An eight-oared racing shell.
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.