informal sanction

Meaning: An informal sanction is an unofficial social reaction to someone's conformity or deviance, delivered by peers, family or community rather than by an institution with written rules. Examples include a smile, praise, a stare, gossip, ridicule and shunning. It can be positive (rewarding conformity) or negative (punishing deviance). It works as social control: approval and disapproval push people toward the group's norms.

On the MCAT: A passage describes a behavior and a response, and you classify the response as formal or informal and as positive or negative. Ask who delivers it and whether it is codified. A fine, arrest, expulsion, diploma or employee award is formal; a raised eyebrow or a compliment is informal. Informal sanctions typically enforce folkways and many mores, while laws carry formal sanctions, though a serious violation can draw both. Expect links to deviance, social control and norms.

Common confusion: Informal does not mean mild, and sanction does not mean punishment. Ostracism by a community can be severe, and a trophy is a formal positive sanction. The deciding fact is whether the response is official and institutionally administered, not how strong or pleasant it is.