The in-bed mathematics that one performs in order to calculate how many hours or minutes they will be able to sleep for if they fall asleep immediately. Usually this is done in desperation after failing multiple attempts at falling asleep. The calculations usually begin while uncomfortably lying awake and trying to force yourself to sleep, you use the time you intend to sleep by and the time you have to get up, and all time in between is the Mathematress calculated sleep time.

A buzz word being used to refer to creators and influencers forming or encouraging unhealthy relationships with their fans. Usually used in the context of young audiences feeling they have a relationship with the influencer due to the huge amount of the influencer’s content they consume. The influencer in question, however, is unaware of the fan’s existence other than the general knowledge of having fans. Common examples include Dream and his stans. These relationships are exacerbated by the influencers confirming they have more than a creator-to-viewer relationship.

The word is circulating due to various YouTube essays about the phenomenon using the word, and therefore people who enjoy complaining about influencers repeating what they heard in the video in any comments section they can find.