The words wean, ween sound the same but have different meanings and spellings. Why do wean, ween sound the same even though they are completely different words?
The answer is simple: wean, ween are homophones of the English language.
To accustom (the young of a mammal) to take nourishment other than by suckling.
To detach from that to which one is strongly habituated or devoted: She weaned herself from cigarettes.
To accustom to something from an early age. Often used with on: "The northerners among the refugees ... were weaned on harsh weather and infertile soils and are known for their rigorous work ethic” ( Lowell Weiss).
Archaic To think; suppose.
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.