The words pole, poll sound the same but have different meanings and spellings. Why do pole, poll sound the same even though they are completely different words?
The answer is simple: pole, poll are homophones of the English language.
Either extremity of an axis through a sphere.
Either of the regions contiguous to the extremities of the earth's rotational axis, the North Pole or the South Pole.
Physics A magnetic pole.
Electricity Either of two oppositely charged terminals, as in an electric cell or battery.
The casting and registering of votes in an election.
The number of votes cast or recorded.
The place where votes are cast and registered. Often used in the plural with the.
A survey of the public or of a sample of public opinion to acquire information.
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").