1. the extent to which someone or something (a trait, attribute, or the like) is admired or considered valuable within a social group.

2. the bias or tendency of individuals to present themselves in a manner that will be viewed favorably by others. In an experiment, for example, it manifests as the social desirability response set, which is the tendency of participants to give answers that are in accordance with social norms or the perceived desires of the researcher rather than genuinely representative of their views. This is a confound to be controlled for in certain research, as it often reduces the validity of interviews, questionnaires, and other self-reports. See impression management; Marlowe–Crowne Social Desirability Scale.