The words taupe, tope sound the same but have different meanings and spellings. Why do taupe, tope sound the same even though they are completely different words?
The answer is simple: taupe, tope are homophones of the English language.
A brownish gray.
To drink (liquor) habitually and excessively or engage in such drinking.
A small, rough-skinned, widely distributed shark (Galeorhinus galeus) having an elongated conical snout.
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").