What is the name of the maximum number of offspring that one individual can produce in a lifetime?

Answer: the biotic potential of the species.
The biotic potential of a species differs from species to species. Examples: a female elephant gives birth to about 5-6 new individuals in her entire life, but a cod spawns in the millions. The biotic potential also differs in different populations of the species. Examples: a vole of the forest population gives 5-9 cubs on average per litter, while a female vole of the arable population produces more offspring – 7-13 cubs. The highest biotic potential is in species that have a high mortality rate, otherwise these species would disappear.