One of the mysteries of the English language finally explained.
Definition of superregeneration in US English:
superregeneration
noun
1Biology. The regeneration of more tissue than has been removed or damaged, as in the production of supernumerary digits on an amputated limb in urodele amphibians.
2Electronics. Regenerative amplification in which self-oscillation is prevented by repeated quenching of the signal at an ultrasonic frequency.
Origin
Late 19th century; earliest use found in Natural Science: a monthly review of scientific progress. From super- + regeneration.