**SJW**: SJW stands for "[Social Justice Warrior]", however its actual meaning has changed several times, and even now depends on context.
Originally the term was positive, with figures such as [Martin Luther King Jr]. and [Mahatma Gandhi] being described as such when praised for their work in bringing justice and equality to oppressed groups. Examples of its use as a term of praise go back as far as 1824, and this continued to be the meaning of the term up until around 2011.
In 2011 several events, primarily [Gamergate], led to the term becoming a pejorative. Many began to use the term to describe people who were overly sensitive and quick to insult anyone who said something they perceived as attacking or oppressing some group of people, even when it wasn't warranted. Basically, anyone who overreacted to a perceived slight against a person or group of people.
However, the term has continued to evolve. While the previous definition sometimes applies, it's now often used simply as an excuse to dismiss things other people say without having to think about them at all, regardless of whether or not they have a valid point. In other words, it's increasingly used as if it's a "get out of jail free" card for insulting entire groups of people. This watering down of the meaning is slowly turning the term into a meaningless insult.
*Early: "The late Reverend [King's] work as a social justice warrior helped lead to the integration of all races in our schools today."
Mid: "All I said was that maybe she overreacted, and the SJW accused me of oppressing all women!"
Late: "She should get off YouTube and make me a sandwich. And before any of you [SJWs] complain, it's [just a joke]."*
*(<http://sjw.urbanup.com/11889591>)* *9 more results*
