dominant

The fifth major tone of a musical scale (five major steps above the note in question); thus G is the dominant of C, A of D, and so on.

The triad built on the dominant tone.

A gene that is dominant.

A species or organism that is dominant.

Ruling; governing; prevailing

"The dominant party controlled the government."

Predominant, common, prevalent, of greatest importance.

"The dominant plants of the Carboniferous were lycopods and early conifers."

Designating the follicle which will survive atresia and permit ovulation.