The words gibe, jibe sound the same but have different meanings and spellings. Why do gibe, jibe sound the same even though they are completely different words?
The answer is simple: gibe, jibe are homophones of the English language.
To make taunting, heckling, or jeering remarks.
To deride with taunting remarks.
A derisive remark.
To shift a fore-and-aft sail from one side of a vessel to the other while sailing before the wind so as to sail on the opposite tack.
To cause (a sail) to jibe.
The act of jibing.
Informal To be in accord; agree: Your figures jibe with mine.
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.