What is oh my days meaning?

"Oh my days" is an expression that is commonly used in British English and it is often used instead of "Oh my goodness" or "Oh my God" to express intense emotions such as surprise, confusion, exasperation or disbelief. It is said to have originated from Cockney rhyming slang, but its exact origin is unclear. The phrase has become quite popular in recent years and is often used on social media, particularly by young people.