What is Regression?
1.
A stress-related defense mechanism. Involves reverting to immature behavior when presented with a stressful situation or hurtful information.
The Europeans were very regressive when they realised that Paris and London had been replaced by New York and Rio de Janiero.
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2.
Roleplay in some way pertaining to age. Sometimes this is "infantilism", which is adults acting as babies. There are all ages.. this can also include schoolgirl or schoolboy with headmaster or headmistress, and every conceivable age in between.
John: Is my little girl ready to play with the big-boys?
Mary: I'm not into regression, get the hell away you perv.
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