The words soccer, socker sound the same but have different meanings and spellings. Why do soccer, socker sound the same even though they are completely different words?
The answer is simple: soccer, socker are homophones of the English language.
A game played on a rectangular field with net goals at either end in which two teams of 11 players each try to drive a ball into the other's goal by kicking, heading, or using any part of the body except the arms and hands. The goalie is the only player who may touch or move the ball with the arms or hands.
Definitions from The American Heritage® Dictionary of the English Language, 4th Edition, from The Century Dictionary and Cyclopedia 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").