1. 占支配（或统治）地位的;占优势的;显著的
    Someone or something that is dominant is more powerful, successful, influential, or noticeable than other people or things.

dominant的反义词

    e.g. ...a change which would maintain his party's dominant position in Scotland...
           将使他的政党在苏格兰继续占据支配地位的变化
    e.g. She was a dominant figure in the French film industry.
           她在法国电影界是个举足轻重的人物。

2. (基因)显性的，优势的
    A dominant gene is one that produces a particular characteristic, whether a person has only one of these genes from one parent, or two genes, one from each parent.

    e.g. Because it is carried by a dominant gene, an affected individual can expect about half of his or her children to inherit the illness.
           因为它是由显性基因携带，所以感染者的孩子会有约50％的可能性遗传该疾病。