Be careful what words you tweet, guys. You may be responsible for ruining English.

Merriam-Webster just added about 1,700 new words to their unabridged American dictionary. You can blame the Internet for creating, spreading, and popularizing at least a handful of them.

Here are some of Merriam-Webster’s new additions and their definitions:

WTF. “What The [eff], used especially to express or describe outraged surprise, recklessness, confusion, or bemusement.”

NSFW. “Not Safe For Work, used to warn someone that a website, email attachment, etc. is not suitable for viewing at most places of employment.”

Jeggings. “A legging that is designed to resemble a tight-fitting pair of denim jeans and is made of a stretchable fabric.”

Photobomb. “To move into the frame of a photograph as it is being taken as a joke or prank.”

Meme. “An idea, behavior, style, or usage that spreads from person to person within a culture.”

Clickbait. “Something, such as a headline, designed to make readers want to click on a hyperlink, especially when the link leads to content of dubious value or interest.”

Emoji. “Any of various small images, symbols, or icons used in text fields in electronic communication to express the emotional attitude of the writer, convey information succinctly, communicate a message playfully without using words, etc.”

Sriracha. “A pungent sauce that is made from hot peppers pureed with usually garlic, sugar, salt, and vinegar and that is typically used as a condiment.”

Twerk. “Sexually suggestive dancing characterized by rapid, repeated hip thrusts and shaking of the buttocks, especially while squatting.”