Definition of "based"

Founded on; having a basis; often used in combining forms.  examples

simple past and past participle of base

1. Being derived from (usually followed by on or upon).  examples

2. Having a base  examples

3. Having a base of operations.  examples

(slang, of a person) Not caring what others think about one's personality, style, or behavior; focused on maintaining individuality.  quotations

(Internet slang) Admirable; praiseworthy.

1. (Internet slang, originally 4chan) Admirable for rejecting liberalism or socially progressive values.  quotations

   Quotations

   • Those who are against Trump are not based at all. On February 16th, The Donald users comment on a “based” post in r/DankMemes which uses a classic Squidward sleeping meme to criticize those who are upset by Chris Pratt going to “church” (one which was purportedly anti-LGBT) but “ok” with sex predators in Hollywood: […]

     2019, Kira Stalker, "The Fracturing of the Alt Right: Conflicting Online Discourses Of White Nationalist Communities", thesis submitted to George Mason University, page 139

   • His [Brenton Tarrant's] meme-themed shooting greatly represents the spirit of the aussie people, in the sense of shitposting until their last moment, based and redpilled he is.

     2019, anonymous, quoted in Cathrine Thorleifsson, "From cyberfascism to terrorism: On 4chan/pol/ culture and the transnational production of memetic violence", Nations and Nationalism, Volume 28, Issue 1, page 293

   • Then, in the same month, noted feminist Christina Hoff Sommers was branded “white supremacy-adjacent” by feminist Roxane Gay. Her reasoning? That our beloved “Based Mom” once appeared at an event with Milo Yiannopoulos and didn't disavow him enough.

     2020, David Rubin, Don't Burn This Book: Thinking for Yourself in an Age of Unreason, unnumbered page

(Internet slang) Indicating emphatic approval of a statement or opinion.