Definitions in relation to their use in kangaroo words, taken from Google Dictionary, and edited for formatting.
Kangaroo word: primogenitor
Joey word: progenitor
primogenitor (noun): an ancestor, especially the earliest ancestor of a people.
progenitor (noun): a person or thing from which a person, animal, or plant is descended or originates.
The letters P, R, O, G, E, N, I, T, O, and R found within the kangaroo word “primogenitor” arrange in the listed order to complete the joey word “progenitor”. While a word can have multiple definitions, in relation to their use with kangaroo words, these two words share a similar meaning: an ancestor.