Literal translation
To go off into biberine
Meaning
to fade away, weaken, wither
Explanation
To dilute, weaken, waste away, or to lose one's mind and slip back into childhood. Biberine was a children's candy sold in bakeries, a colored, flavored powder dissolved in water, popular between the 1940s and 1970s. The word carries the Latin root biber, to drink, as in biberon, baby bottle. To leave in biberine is thus to dilute, to lose one's substance, a sense that, applied to a person, slides toward senility through the word's childish connotation.