The meaning of fr is “for real”.
It is used to affirm or inquire about the legitimacy of statements and stories, usually in text messages.
Apart from the meaning above, “Fr” is also frequently used to refer to France.
“Fr” as a shortened form of “for real” was introduced to English during the 90’s, when chatrooms and forums were starting to get populated by people new to the internet.
In the 2000’s, it got further integrated into the lingo through text messages.
The expression was first defined on Urban Dictionary in 2003 and several other sites had mentioned the acronym since then.
Today, “fr” is a popular abbreviation in texting, as well as tweets and other social media posts.