In social philosophy, objectification is the act of treating a person as an object or a thing. Sexual objectification, the act of treating a person as a mere object of sexual desire, is a subset of objectification, as is self-objectification, the objectification of one's self. In Marxism, the objectification of social relationships is discussed as "reification".

According to Martha Nussbaum, a person is objectified if one or more of the following properties are applied to them:

Rae Langton proposed three more properties to be added to Nussbaum's list:

Nussbaum found the general understanding of objectification was too simplistic to be useful as a normative concept to evaluate the moral implications of sexualization of women. She attempts to remedy this by distinguishing between benign and harmful forms of objectification in different circumstances relative to sex. Nussbaum considers objectification not just significant when considering sexuality, which has been discussed at length, but also an important component of the Marxist view on capitalism and slavery. She argues that not all forms of objectification are necessarily inherently negative, and that objectification is not necessarily a foregone conclusion when one of the seven properties is present.

According to Immanuel Kant's theories, sexual desire is inherently objectifying, as a strong sexual urge includes a desire to engulf another person for sexual satisfaction. This desire manifests as a desire to control the target's behaviour to secure one's own satisfaction, effectively denying the target's autonomy. The intensity of sexual desire also reduces subjectivity by drowning out consideration of the target's thoughts or feelings in the pursuit of one's own satisfaction, reducing other people to a set of body parts intended to provide gratification. In short, sexual objectification is a general feature of sexuality, in that the involved parties eagerly desire both to objectify and be objectified.

Catherine Mackinnon and Andrea Dworkin adopt Kant's understanding of sex as inherently objectifying, but disagree that participants are objectifiers and objectified in similar proportion; rather, it is asymmetrical. Because sexuality exists within a larger social and culture context and men and women are not granted power equally within that context, this heavily influences the dynamic. According to Mackinnon and Dworkin, male sexuality is expressed dominantly via objectifying others, while female sexuality is expressed submissively via accepting objectification or engaging in self-objectification. In this context, women are more vulnerable to violability and lack of subjectivity and autonomy. Mackinnon and Dworkin ignore personal histories and psychologies that Nussbaum considers equally morally important to the construction of male and female sexualities.

While male gaze is one of the main enablers of self-objectification, social media is a medium that heavily promotes and enforces self-objectification, especially in women. Women post selfies on social media from camera angles that typify the male gaze perspective, while the comments section provides a forum for viewers to voice disapproval or praise. Positive feedback brings a sense of validation to women who post these selfies and reinforces the behaviour.

The objectification theory proposed by Barbara Fredrickson and Tomi-Ann Roberts analyzes the female body with consideration to the psychology of women and gender. They assert that objectifying a woman or a girl can cause an increased feeling of anxiety or self-awareness in her, thus affecting her mental health. As a result of this objectification, the target adopts the status that society has given to her as her primary view of herself. In their words: "Perhaps the most profound and pervasive of these experiences is the disruption in the flow of consciousness that results as many girls and women internalize the culture's practices of objectification and habitually monitor their bodies' appearance."