Honestly, one day you’ve never heard of a word, and the next it’s everywhere. How does that happen?
Gaslighting is a colloquialism, loosely defined as manipulating someone so as to make them question their own reality. The term derives from the title of the 1944 American film Gaslight, though the term did not gain popular currency in English until the mid-2010s.
The term may also be used to describe a person (a “gaslighter”) who presents a false narrative to another group or person, thereby leading them to doubt their perceptions and become misled, disoriented or distressed. Oftentimes this is for the gaslighter’s own benefit. Normally, this dynamic is possible only when the audience is vulnerable, such as in unequal power relationships, or fearful of the losses associated with challenging the false narrative.Wikipedia
Gaslighting, therefore, is nothing new, and the politicians have been gaslighting us for years. But Trump has made it an art form, and that is why this word has become meaningful in the last decade.
I rest my case, m’lord.