The pronunciation is exactly the same for both spellings, but the US convention tends to write it as you hear it. You hear 'z', so you write 'z'. And yes, this happens to many many English words. What's important is not to mix the styles: "I apologize, I didn't realize that." (US English, perfectly OK) "I apologise, I didn't realise that." (UK English, perfectly OK) "I apologize, I didn't realise that." (Big mistake!! You sound confused.)

apologize = American spelling apologise = British spelling There are hundreds of words like this.

Definitions of pologize: verb acknowledge faults or shortcomings or failing Example: He apologized for the many typoes defend, explain, clear away, or make excuses for by reasoning Example: he rationalized his lack of success Definitions of apologise: verb defend, explain, clear away, or make excuses for by reasoning Example: he rationalized his lack of success acknowledge faults or shortcomings or failing Example: He apologized for the many