What term describes sexual activity that involves some form of asphyxia to enhance pleasure?

The term that describes sexual activity involving asphyxia to enhance pleasure is autoeroticism. This practice can include various methods, such as restricting airflow, and is often done either alone or with a partner. The primary aim is to intensify sexual arousal or orgasm by creating a heightened state of excitement through the combination of pleasure and asphyxia.

In contrast, intimacy refers to close, personal relationships and does not specifically imply any particular sexual activity or method of enhancement. Fetishism is characterized by a strong sexual attraction to a specific object, material, or body part, but it does not inherently involve asphyxia. Voyeurism involves gaining sexual pleasure from observing others in sexual activities without their knowledge, which is unrelated to any form of asphyxia. Thus, autoeroticism is the terms that directly aligns with the description provided in the question.