Any human persons who have succeeded in physical survival from infancy, but are socially and psychologically conditioned to remain, or stay, as intellectual "babies."

A Staybie (singular) has many evolutionary advantages including, but not limited to, continual comfort, social coddling, and mating success.
"How can Karen possibly believe that Boss will buy that lame excuse?"
"Bro, Karen and Boss are Staybies, they will always just gurgle and roll on their backs no matter what actual problem happens."
by Nicholas the 2 April 19, 2019
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