The words hangar, hanger sound the same but have different meanings and spellings. Why do hangar, hanger sound the same even though they are completely different words?
The answer is simple: hangar, hanger are homophones of the English language.
A shelter especially for housing or repairing aircraft.
One who hangs something: a house painter who also works as a paperhanger.
A contrivance to which something hangs or by which something is hung, as:
A device around which a garment is draped for hanging from a hook or rod.
A loop or strap by which something is hung.
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.