“Here are some terms they use, and other hallmarks to look out for:

Human biodiversity: Despite the fact that many say racism is at the heart of its platform, the alt-right is very sensitive about being called racist. They use the term “human biodiversity” as a more scientific-sounding way of referring to issues of race.

Libtard: The alt-right revels in the rejection of “political correctness,” so embracing an outdated term for a person with an intellectual disability (“retard”) serves the purpose of insulting liberals.

Memes: The modern alt-right originated in places like 4chan and 8chan, which are hubs for meme creation. Meme creation is still a centerpiece of the movement. The alt-right is responsible for getting the Pepe the Frog meme classified as a hate symbol.

Political correctness: Anything that challenges an alt-right person’s right to say whatever they want, whenever they want, in any way they want to say it. According to the alt-right, political correctness is responsible for most of society’s ills, including feminism, Islamic terrorism and overly liberal college campuses.

Snowflake: Short for “special snowflake,” a pejorative for an entitled person. Most people protesting Trump are “snowflakes,” according to the alt-right, as are anti-Trump celebrities and most liberals.”

Source is provided below (which also contains more terms):

Analysis: ‘Cuck,’ ‘snowflake,’ ‘masculinist’: A guide to the language of the ‘alt-right’:
https://www.latimes.com/nation/la-na-pol-alt-right-terminology-20161115-story.html