The words whining, wining sound the same but have different meanings and spellings. Why do whining, wining sound the same even though they are completely different words?
The answer is simple: whining, wining are homophones of the English language.
Present participle of whine.
gerund of whine
Present participle of wine.
Definitions from Wiktionary, Creative Commons Attribution/Share-Alike License and Wordnik.
Homophones (literally "same sound") are usually defined as words that share the same pronunciation, regardless of how they are spelled.