There is no actual name. They are just refered to as dominant or pushy.
a gerbil is called a gerbil
The dominant figure is always the "alpha" male.
The "Alpha Female"
It means the leader of a wolf pack. Usually the alpha (leader) of a wolf pack is a male so they just call it an alpha male. Sometimes though, rarely, a she-wolf is known to be the alpha. An alpha male can also mean the male wolf who can produce pups, but that is usually the leader (the alpha male). I also think that the alpha she-wolf is the she-wolf who can bear pups, or the mate of the alpha (leader).
It means your Gerbil is overweight and eing regular sized or your gerbil is dying. - GerbilExpert
An "Alpha pair" is the dominant breeding pair in a pack of animals. This is usually a normality in wolf packs. Only the alpha female and alpha male are allowed to have offspring.
It all depends on what you feel is best for your gerbil. You can call it any name you want.... someone I know named hers after brands: Hershey, Snickers, Reeses, etc.
A wolf can't just become dominant. Either they are submissive oir dominant. No matter how low they are, they always try to climb higher in the pack and challenge their position. Wolves seem to love being alpha.
It is probably because it is dominant of its sister. If this gets much worse it might be an idea to separate them. My friends gerbil bit off its brothers tail... so... this is something you need to watch.
An alpha is the first letter of the Greek alphabet, an dominant male within a group of animals, or the first of a number of things in order of preference.
because it dominates the phenotype
Alpha: lead, leader, head, regal Dominant male. Or maybe: Top dog!