How is language evolving on the internet? In this series on internet linguistics, Gretchen McCulloch breaks down the latest innovations in online communication.

Here's a word that you might not have noticed before: lowkey. A great example is this tweet:

Although of course the picture was originally taken for other reasons, if we assume that the actors in this photo were actually trying to get their waiter's attention, it's a great illustration of what it looks like to do something lowkey. They're not beckoning widely at the imaginary waiter or calling out that something's caught on fire—no, it's not urgent, they're playing it cool, making some eye contact, waiting for the waiter to notice them. 

It's pretty clear where lowkey comes from. Mainstream dictionaries, such as Merriam-Webster, have low-key with a hyphen, as in a low-key party.

low–key (adjective)

: quiet and relaxed : not very forceful, emotional, or noticeable

In fact, even Urban Dictionary has "low key" with the same meaning in 2005: 

low key

keep something low key: to not announce it; to have a quiet gathering; opposite of a large party or big group of people; not much emphasis, closely aligned with a normal night out doing the usual stuff.

im going out tonight but it's pretty low key; work tomorrow so tonight's going to be a low key event.
by donjamin June 10, 2005

There's also a "low-key" that's used in photography, where it means "dark, with little or no fill light and high lighting ratio," which may be where "low-key" as in "low-key party" came from (sources are unclear on this though.) 

In any case, there's a clear connection to the new lowkey: meaning-wise, the ideas of quiet/relaxed and kinda/subtly aren't so far apart. But while old low-key is an adjective (a low-key party, that party was low-key), new lowkey is an adverb. It's not even that new—it shows up in Urban Dictionary from 2009

Lowkey
Meaning kinda

I was lowkey excited about the party.
i was kinda excited about the party.

by lUXURyLala August 29, 2009

1) Secretly or discretely

2) Slightly or kinda

"He's moving to Chicago in three weeks but the semester isn't over for another seven weeks. He's lowkey dropping out."

"I didn't think I would be but I'm lowkey sad that my roommate is moving out."

Adverb lowkey is really common online, but I couldn't find anyone analyzing or commenting on it yet, and also it hasn't yet made its way into dictionaries (psst, any lexicographers reading this?). Here are a few more examples from twitter: 

finding nemo is lowkey one of my all time favorite movies 

british people r so intolerant of each other we all lowkey want each other dead

i wish one of my lowkey crushes had a lowkey crush on me so we could like lowkey make out and stuff

When you're lowkey sad af but trying not to care

And unlike the "low-key party" meaning, new lowkey also has an opposite: highkey. Although highkey isn't nearly as common as lowkey, there are still lots of examples. People on Twitter often use it to talk about unrequited crushes:

lowkey in love with you highkey never gonna let you know

lowkey want a relationship highkey don't wanna be disappointed

I'm highkey about you, but trying to be lowkey about you

In a way, it's fitting that lowkey has been around for at least six years but it hasn't been documented outside Urban Dictionary and a few obscure sites. It's just been lowkey waiting for us to notice it.