Therapy-Speak
“Pop psychology” refers to terms and concepts from the field of psychology that have been popularized in mainstream culture, often via bestselling books, TV shows, advice columns, and/or social media influencer accounts.
Occasionally these terms are translated to a wider audience in their totality, but often they're simplified or misconstrued by the intermediaries who share them, and their common meaning is thus distinct from their actual, medical definition.
We might casually call someone a narcissist, or instance, if they seem self-involved, but actual narcissistic personality disorder is a far more specific (and rare) thing, segmented into "grandiose" and "vulnerable" subtypes, and defined by aggression, boldness, and grandiosity in the former case, and defensiveness and hypersensitivity in the latter.
Someone who likes to take selfies and who seems to care more about their own issues and concerns than those of their friends or family, then, is not a narcissist in the clinical sense, but may be dubbed a narcissist by those who know them—a flattening and broadening of the term that can still be useful in some cases, but which arguably waters-down the utility of the more formal (and technically correct) version of the word.
