What is another word for plain as day?
Pronunciation: [plˈe͡ɪn az dˈe͡ɪ] (IPA) 
The phrase "plain as day" is used to describe something that is obvious or easy to see. There are several synonyms that can be used in place of this phrase. One possibility is "clear as crystal," which means the same thing but uses a different simile. Another option is "visible to the naked eye," which emphasizes that there is no need for special equipment or effort to see the thing in question. "Unmistakable" is another possible synonym, implying that there is no doubt or confusion about what is being discussed. In short, there are many ways to express the concept of something being clear and obvious.
