Is "gaslighting" a mainstream concept in the cognitive sciences? The term "gaslighting" (referring to abusive manipulation of the facts to confuse victims) is common in pop-psychology sources, and I have friends who report that their psychologists or psychiatrists use the term as some form of shorthand.

However, I have looked in a couple of online psychology dictionaries, and they don't define the term. 

I have looked on this site, and it only appears once.

I have looked on Google Scholar. While I can find some references to the term - especially a "seminal" 1981 paper, Some clinical consequences of introjection: gaslighting, there don't appear to be many papers referencing it, and I haven't the experience to evaluate whether they are fringe ideas or mainstream science.

Is gaslighting just pop psychology, or is the concept of gaslighting widely accepted in the cognitive sciences?
The wikipedia article you linked to regarding the term Gaslighting has references to clinical and research literature.

Dorpat, (1996) talks about the incidences of Gaslighting conducted by therapists.


  In treatment, the psychotherapist is in a position of power. Often, this power is unintentionally abused. While trying to embody a compassionate concern for patients, therapists use accepted techniques that can inadvertently lead to control, indoctrination, and therapeutic failure. Contrary to the stated tradition and values of psychotherapy, they subtly coerce patients rather than respect and genuinely help them. The more gross kinds of patient abuse, deliberate ones such as sexual and financial exploitation, are expressly forbidden by professional organizations. However, there are no regulations discouraging the more covert forms of manipulation, which are not even considered exploitative by many clinicians.


Jacobson &amp; Gottman, (1998) talks about wife batterers.


  After their decade of research with more than 200 couples, the authors conclude that not all batterers are alike, nor is the progression of their violence always predictable. But they have found that batterers tend to fall into one of two categories, which they call "Pit Bulls" and "Cobras". Pit Bulls, men whose emotions quickly boil over, are driven by deep insecurity and an unhealthy dependence on the mates whom they abuse. Pit Bulls also tend to become stalkers, unable to let go of relationships that have ended.
  
  Cobras, on the other hand, are cool and methodical as they inflict pain and humiliation on their spouses or lovers (Source: Google Books synopsis)


In the book, it says


  A tactic of emotional abuse that is common among Pit Bulls, but not Cobras, is the phenomenon known as "gaslighting."  (The term comes from the film Gaslight, in which Charles Boyer convinces Ingrid Bergman that she is going insane.)  We gave an example of this phenomenon with Dave and Judy, in which he blatantly denied that he was a batterer.  Gaslighting is a systematic attach on the wife's perception of reality.


The term has been used in articles I have read within the last few months including one by Christine Louis de Canonville (2017) who has a B.A. (Hons.) degree in Psychology, and Sarkis (2017) within PsychologyToday.

If you search Google Scholar, the site will return thousands of results including articles in therapy journals, so the concept of gaslighting is widely accepted in the cognitive sciences.

References

Dorpat, T. L. (1996). Gaslighting, the Double Whammy, Interrogation, and Other Methods of Covert Control in Psychotherapy and Psychoanalysis. New York:Jason AronsonISBN-10: 1-5682-1828-1ISBN-13: 978-1-5682-1828-1

Jacobson, N. S. &amp; Gottman, J. M. (1998). When Men Batter Women: New Insights into Ending Abusive Relationships. New York:Simon and SchusterISBN-10: 1-4165-5133-6ISBN-13: 978-1-4165-5133-1

Louis de Canonville, C. (2017). The Effects of Gaslighting on Victims of Narcissistic Abuse [Online]Available at: http://narcissisticbehavior.net/the-effects-of-gaslighting-in-narcissistic-victim-syndrome/

Sarkis, S. (2017) Are Gaslighters Aware of What They Do? [Online]Available at:https://www.psychologytoday.com/blog/here-there-and-everywhere/201701/are-gaslighters-aware-what-they-do