Here are the related words I know. - 요대 - this is not a common word at all. No one seems to use it nowadays. - 허리띠 - common but not the most common. 띠 is somewhat vague as it can mean anything wrapped around the waist. - 혁대 (leather(혁) belt) - this used to be the most common word for waist belt, especially for men. - 벨트 ("belt") - this borrowed word has been gaining popularity. I think it's the most common word these days.

the latter. the former is a little bit outdated so it's used by the elder generally.