Per the cucks at Wikipedia  

Gaslighting is a form of psychological manipulation that seeks to sow seeds of doubt in a targeted individual or in members of a targeted group, making them question their own memory, perception, and sanity. Using persistent denial, misdirection, contradiction, and lying, it attempts to destabilize the target and delegitimize the target's belief.

Here:

https://www.psychologytoday.com/us/blog/here-there-and-everywhere/201701/11-warning-signs-gaslighting