The meaning of icymi is “in case you missed it”.
Seen in the posts and messages, in which the author is spoiling our favorite series just when we did miss it.
The origin of the abbreviation is not fully clear, although, similar to other internet acronyms, it was conceived sometime during the 90’s, on the message boards and chatrooms of the time.
Its first mention on Urban Dictionary dates back to 2006, the year when Twitter was founded.
“Icymi” was introduced to the masses and popularized by Twitter.
During the 2010’s, the expression, however, spread onto various other social media outlets, such as Facebook or Instagram as it became a fashionable hashtag.