noun
dominant character; dominant trait
Technical term in genetics for a trait that is expressed when at least one dominant allele is present. Contrasts with 劣性形質 (recessive trait).
メンデルの実験では、丸い種子が優性形質として現れた。
In Mendel's experiments, round seeds appeared as the dominant trait.
Compound of 優性 (dominance) and 形質 (trait, character). The term was coined in the context of modern genetics to translate 'dominant character'.