Concept creep is the process by which harm-related topics experience semantic expansion to include topics which would not have originally been envisaged to be included under that label.^[1] It was first identified by Nick Haslam in 2016, who identified its effects on the concepts of abuse, bullying, trauma, mental disorder, addiction, and prejudice.^[2] Others have identified its effects on terms like "gaslight"^[3] and "emotional labour".^[4] The phenomenon can be related to the concept of hyperbole.^[5]

It has been criticised for making people more sensitive to harms^[6] and for blurring people's thinking and understanding of such terms, by categorising too many things together which should not be, and by losing the clarity and specificity of a term.^[4]

Although the initial research on concept creep has focused on concepts central to the political left's ideology, psychologists have also found evidence that people identifying with the political right have more expansive interpretations of concepts central to their own ideology (ex. sexual deviance, personal responsibility and terrorism).^[7]

According to Haslam, there are two explanations for why concept creep has trended in favor of greater sensitivity towards harm: the first being "just as successful species increase their territory, invading and adapting to new habitats, successful concepts and disciplines also expand their range into new semantic niches" and the second being "Psychology has played a role in the liberal agenda of sensitivity to harm and responsiveness to the harmed ... and its increased focus on negative phenomena ... has been symptomatic of the success of that social agenda."^[6]