dominant

noun

1. 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.
2. The triad built on the dominant tone.
3. Of an allele, that a heterozygote for the allele has the same phenotype as the homozygote.

   “Finally, if we suppose provisionally that the mutant genes are dominant just as often as they are recessive, selection will be far more severe in eliminating the disadvantageous dominants than in eliminating the disadvantageous recessives.”

4. A species or organism that is dominant.

   “Landowners cannot afford to cut submerchantable trees, yet many hesitate to cut merchantable dominants and codominants at the risk of downgrading the residual stand.”

5. The dominating partner in sadomasochistic sexual activity.

   “This calendar is not for the faint of heart (unless you have some strong butch dominant to hold you while you swoon)”

   “His story was a fable you told dominants in training to stress the importance of comprehending the depths of your submissive's needs.”

adj

1. Ruling; governing; prevailing

   “The dominant party controlled the government.”

   “The member of a dominant race is, in his dealings with the subject race, seldom indeed fraudulent, […] but imperious, insolent, and cruel.”

2. Predominant, common, prevalent, of greatest importance.

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

   “All other elements are mere "impurities" when their abundances are compared with those of these two dominant elements.”

   “It's the water that makes this area famous. […] That water is still being used to supply Blackford's two dominant industries, Tullibardine whisky distillery to the south of the village and, more significantly, Highland Spring Group's bottling plant to the north.”

3. Preferred and used with greater dexterity than the other, as the right hand of a right-handed person or the left hand of a left-handed one.
4. Designating the follicle which will survive atresia and permit ovulation.
5. Being the dominant

   “Dominant seventh”