NEW YORK (AP) — “Gaslighting” — behaviour that’s mind manipulating, grossly misleading, downright deceitful — is Merriam-Webster’s word of the year.

Lookups for the word on merriam-webster.com increased 1,740 per cent in 2022 over the year before. But something else happened. There wasn’t a single event that drove significant spikes in curiosity, as it usually goes with the chosen word of the year.

The gaslighting was pervasive.

“It’s a word that has risen so quickly in the English language, and especially in the last four years, that it actually came as a surprise to me and to many of us,” said Peter Sokolowski, Merriam-Webster’s editor at large, in an exclusive interview with The Associated Press ahead of Monday’s unveiling.

“It was a word looked up frequently every single day of the year,” he said.

Merriam-Webster’s top definition for gaslighting is the psychological manipulation of a person, usually over an extended period of time that “causes the victim to question the validity of their own thoughts, perception of reality, or memories and typically leads to confusion, loss of confidence and self-esteem, uncertainty of one’s emotional or mental stability, and a dependency on the perpetrator.”

More broadly, the dictionary defines the word thusly: “The act or practice of grossly misleading someone especially for one’s own advantage.”

Gaslighting is a heinous tool frequently used by abusers in relationships — and by politicians and other newsmakers. It can happen between romantic partners, within a broader family unit and among friends. It can be a corporate tactic, or a way to mislead the public. There’s also “medical gaslighting,” when a health care professional dismisses a patient’s symptoms or illness as “all in your head.”

Despite its relatively recent prominence — including “Gaslighter,” The Chicks’ 2020 album featuring the rousingly angry titular single — the word was brought to life more than 80 years ago with “Gas Light,” a 1938 play by Patrick Hamilton.

It birthed two film adaptations in the 1940s. One, George Cukor’s “Gaslight” in 1944, starred Ingrid Bergman as Paula Alquist and Charles Boyer as Gregory Anton.

Merriam-Webster, which logs 100 million pageviews a month on its site, chooses its word of the year based solely on data. Sokolowski and his team weed out evergreen words most commonly looked up to gauge which word received a significant bump over the year before.

They don’t slice and dice why people look up words, which can be anything from quick spelling and definition checks to some sort of attempt at inspiration or motivation. Some of the droves who looked up “gaslighting” this year might have wanted to know, simply, if it’s one or two words, or whether it’s hyphenated.

“Gaslighting,” Sokolowski said, spent all of 2022 in the top 50 words looked up on merriam-webster.com to earn top dog word of the year status. Last year’s pick was “vaccine.” Rounding out this year’s Top 10 are: Oligarch, driven by Russia’s invasion of Ukraine, Omicron, codify, Queen consort, Raid, Sentient, Cancel culture, LGBTQIA, and Loamy.