The term "Postmodern philosophy" entered the academic lexicon in the late 20th century, around the 1970s and 1980s, with philosophers like Jacques Derrida, Jean-François Lyotard, and Jean Baudrillard contributing to its development. Postmodern philosophy challenges traditional notions of truth, knowledge, and rationality, emphasizing the role of language, power, and interpretation in shaping our understanding of reality.