Final answer:
Microexpressions are brief, involuntary facial expressions that indicate emotion. These expressions are typically fleeting and often reveal true feelings that a person might be attempting to conceal.
Step-by-step explanation:
The nonverbal term for brief flashes of emotion in the face is known as microexpressions. Microexpressions are brief, involuntary facial expressions that occur when a person experiences an emotion. They are extremely rapid and last only a fraction of a second. For example, a flash of disgust on a person's face when they smell something unpleasant, or a brief smile when a person is pleased. These microexpressions are often unconscious and can reveal genuine emotions that a person may be trying to hide.
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