existentialism
noun
ex·is·ten·tial·ism ˌeg-(ˌ)zi-ˈsten(t)-shə-ˌli-zəm 
ˌek-(ˌ)si-
: a chiefly 20th century philosophical movement embracing diverse doctrines but centering on analysis of individual existence in an unfathomable universe and the plight of the individual who must assume ultimate responsibility for acts of free will without any certain knowledge of what is right or wrong or good or bad
Example Sentences
Recent Examples on the Web Coming of age during climate change and entering the workforce during a pandemic created a larger sense of existentialism for my generation. 
Chloe Berger, Fortune, 7 Aug. 2022 Like Insecure, Rap Sh!t doubles as an incubator for Rae’s thematic interests (friendships between women, career existentialism, the quest for self-worth) and a platform for emerging or under-recognized artists. Lovia Gyarkye, The Hollywood Reporter, 18 July 2022 Herzog has always been attuned to the ways in which survivalism functions as a form of existentialism. Dan Piepenbring, The New Yorker, 16 June 2022 These extended from themes such as existentialism and Marxism to modernist techniques like streams of consciousness. Jordan Michael Smith, WSJ, 27 May 2022 Employees in an environment of philosophical existentialism feel pride, value and loyalty. Kelley Swing, Rolling Stone, 1 Apr. 2022 Movies about the future tend to come in one of two forms, aesthetically: Cold Apple Store (gleaming white surfaces, chilly existentialism) or Unhinged Apocalypse (dust, chaos, primal fear). Leah Greenblatt, EW.com, 3 Mar. 2022 Existential, of course, is linked to existentialism, a focus of Danish philosopher Soren Kierkegaard (1813-55). Peter Funt, WSJ, 1 Feb. 2022 Didn’t Allen learn anything about fidelity, faith, and existentialism from the great European films parodied in Rifkin’s Festival? Armond White, National Review, 4 Feb. 2022 See More
Chloe Berger, Fortune, 7 Aug. 2022 Like Insecure, Rap Sh!t doubles as an incubator for Rae’s thematic interests (friendships between women, career existentialism, the quest for self-worth) and a platform for emerging or under-recognized artists. Lovia Gyarkye, The Hollywood Reporter, 18 July 2022 Herzog has always been attuned to the ways in which survivalism functions as a form of existentialism. Dan Piepenbring, The New Yorker, 16 June 2022 These extended from themes such as existentialism and Marxism to modernist techniques like streams of consciousness. Jordan Michael Smith, WSJ, 27 May 2022 Employees in an environment of philosophical existentialism feel pride, value and loyalty. Kelley Swing, Rolling Stone, 1 Apr. 2022 Movies about the future tend to come in one of two forms, aesthetically: Cold Apple Store (gleaming white surfaces, chilly existentialism) or Unhinged Apocalypse (dust, chaos, primal fear). Leah Greenblatt, EW.com, 3 Mar. 2022 Existential, of course, is linked to existentialism, a focus of Danish philosopher Soren Kierkegaard (1813-55). Peter Funt, WSJ, 1 Feb. 2022 Didn’t Allen learn anything about fidelity, faith, and existentialism from the great European films parodied in Rifkin’s Festival? Armond White, National Review, 4 Feb. 2022 See More Word History
Etymology
existential + -ism, in part as translation of German Existentialismus (or Existenzialismus) or French existentialisme
First Known Use
1941, in the meaning defined above