A one-night stand is a single sexual encounter between individuals, where at least one of the parties has no immediate intention or expectation of establishing a longer-term sexual or romantic relationship. The individuals participating in a one-night stand typically have not known each other long and have had minimal time to get to know each other before engaging in sexual activity. A one-night sexual encounter is not necessarily always a one-night stand; the crucial distinction is the expectation or intention that the relationship will not necessarily be extended beyond the initial sexual encounter. A one-night stand is differentiated from prostitution, as it takes place without money or any coercion. In Western society, there is often a social stigma associated with one-night stands, reflected in the phrase "Walk of shame", wherein a participant in a one-night stand has to go home in the morning wearing clothes that were worn the previous night.

一夜情，英文为“one-night stand”，通常指两个陌生人之间发生的性行为，且双方没有保持长久性关系或恋爱的意愿。参与一夜情的双方通常都亦未有跟对方相处很久，而且并未有十分了解对方。一夜情跟卖淫的主要分别在于双方并没有钱银的交易。在西方社会，一般大众视一夜情为一种耻辱。英语中有“walk of shame”这一词汇，指的是一夜情后，参与者在早上要穿著昨晚所著的衣服回家，是一份令人羞耻的事。1960至1980年代是一夜情最流行的时期。人们要到酒吧、的士高、health club和其他公共场所寻找一夜情