Vibe coding is now in the dictionary — the phrase that reads as a boast or an accusation

Merriam-Webster's September 15, 2026 update put 1,400 new words and definitions into the dictionary, and vibe coding was among them. 1

The entry reads like any other. A noun, pronounced VYB-koh-ding, sometimes spelled vibecoding, meaning "the act or practice of using an artificial intelligence system to generate computer code in a given programming language." 2

That definition describes a way of working, and it withholds judgment on the work. The phrase itself now delivers one, and which judgment you hear depends on who is talking. Software engineers building a weekend app reach for it as a plain description of what they did. Engineering managers, reviewers and maintainers reach for it the way a doctor reaches for a diagnosis. Both usages are current, both are documented, and the second one is the reason the word repays knowing properly.

Merriam-Webster's slang page, updated in June 2026, had defined vibe coding as "writing computer code in a somewhat careless fashion, with AI assistance," then added that the term is "more jargon than slang," with a real chance of drifting in meaning if it stays in use. 6 A dictionary house hedging about a word it has just promoted is ordinary practice. Here the hedge points somewhere real. Vibe coding names a method that practitioners and their reviewers disagree about, which puts it in a different category from most new dictionary words.

Both halves of the phrase come from the pre-computer world, and the two are more than six hundred years apart.

Vibe entered English in 1940 as shorthand for vibraphone, the percussion instrument whose metal bars produce a wavering tone. The plural vibes, in the sense of an instinctive feeling about a person or situation, is attested from 1967 as a shortening of vibration — the same word that describes a string or a nerve moving rapidly back and forth. An eighteenth-century theory held that vibration in the nerves carried impressions from the body to the mind, and the philosopher David Hartley coined vibratiuncle in 1748 for a slight vibration. Oscar Wilde implied the modern sense of vibes as early as 1899, and the word settled into general slang in the late 1960s. 7

Code is far older. It arrived around 1300 from the Old French code, a system of laws, which came from Latin codex, "a systematic classification of statutory law," and earlier caudex, a tree trunk — the wooden tablets a Roman book was made from. Etymonline traces the origin back to a Proto-Indo-European root meaning "cleaved, separate." The sense of a cipher, or a system of signals and the rules governing their use, dates from 1808. The sense of instructions a computer can use dates from 1946, and the verb "to write computer code" from 1987. 8

Line the two histories up and the compound does something tidy. The half meaning an instinctive feeling is the newer half, and it carries the idea of working by feel. The half meaning a code of law is the older half, and it carries the binding, written, reviewable part. A phrase built from a 1960s mood word and a medieval statute book describes a practice that answers to both, which is why it keeps sliding between description and reproach.

Andrej Karpathy published the phrase on February 2, 2025, in a post that has since been viewed 7.3 million times. 5 He was describing his own working habits: talking to a coding model by voice, asking it for "the dumbest things like 'decrease the padding on the sidebar by half' because I'm too lazy to find it," accepting every suggestion without reading the changes, and pasting error messages straight back in. "The code grows beyond my usual comprehension," he wrote. 5

The sentence everyone quotes is the definition: "There's a new kind of coding I call 'vibe coding', where you fully give in to the vibes, embrace exponentials, and forget that the code even exists." The sentence that got left behind sits four lines later: "It's not too bad for throwaway weekend projects, but still quite amusing." 5 Karpathy scoped his own coinage to disposable things he had no intention of maintaining. The phrase escaped that scope within weeks, and the distance between the original limit and the way the term is now used accounts for much of its bite.

Later that February, the New York Times columnist Kevin Roose used the word to describe building small apps with no coding training at all, and wrote that having an idea and a little patience was usually enough. Merriam-Webster's slang page quotes that column directly. 6

The lexicographers followed. Collins named vibe coding its Word of the Year for 2025 on November 6, after watching the term's use rise sharply since February across the 24-billion-word corpus the company monitors, and Alex Beecroft, Collins's managing director, described the choice as capturing "a major shift in software development, where AI is making coding more accessible." 910 Merriam-Webster took the slower route of slang page first, full entry nineteen months after the post, in a batch its editors said reflected "words and meanings that have demonstrated widespread use over time." 1

What the lexicographers recorded was a method under argument. The evidence arrived from three directions, and each piece measures something different.

Each figure counts a different thing: adoption in the first row, elapsed time in the second, review findings in the third. What they share is direction. The promise and the measurement keep landing on opposite sides.

Trade coverage ran the same way. In September 2025, Fast Company declared that "the vibe coding hangover" had arrived, quoting Jack Zante Hays, a senior software engineer at PayPal: "Code created by AI coding agents can become development hell," he said, because the tools spin up features quickly and leave behind bugs and maintenance work. 14

In June 2026, the phrase reached the maintainer of a widely deployed backup tool. Andrew Tridgell, who has maintained rsync for decades, published a response to a storm of criticism over AI-assisted commits in the project, after a release caused regressions for some users. He wrote that he had used AI tools for the mechanical work of rewriting the test suite, that he had designed the suite himself and reviewed every part of it, and he drew the line explicitly: "I did not just vibe-code 'convert test suite to python'." 15

That sentence marks where the word now sits. A developer with forty years of experience, defending work he had checked line by line, reached for vibe coding as the name of the thing he had avoided. The term has become the low end of a scale, useful because it marks the boundary between assisted work that someone stands behind and assisted work that nobody has read.

Vibe coding covers one practice. Several neighbouring terms cover what people often mean instead.

The verb deserves its own note. Vibe code is transitive and intransitive both: you can vibe code a website, and you can say that a team vibe codes. Its inflections follow the base word — vibe coded, vibe coding, vibe codes — and Merriam-Webster records the hyphenated and closed-up spellings as variants of each. 4

The noun is uncountable. Say that you do vibe coding, that you took it up, that you are tired of it. The phrase also works in front of another noun, which is where much of its current life sits: a vibe coding platform, a vibe coding tool, a vibe coding startup. Merriam-Webster's entry flags that attributive use directly. 2

Three sentences, in the register each one belongs to:

That third sentence is the one to be careful with, since a speaker usually aims it at somebody. Turned on a colleague's work in front of other people, vibe coded reports that nobody has read the code.

Before you use the phrase about your own work, answer three questions. Did someone who understood the code review it? Will human beings maintain it? Would its failure cost money, safety, or somebody's privacy? Three yeses mean you are describing ordinary AI-assisted development, and the precise term will make you sound more credible than the fashionable one. Two noes and the word fits, and saying it yourself beats having somebody else say it about you later.

Merriam-Webster's editors left themselves an escape hatch when they wrote that the term might change meaning if people keep using it. 6 The likely direction is already visible. A word that names a method becomes a word that names a standard, and a standard is what you get measured against. Vibe coding entered the dictionary at the point where saying it about your own work stopped being a boast you could make safely. 1