mole

noun [具体名词]鼹鼠；间谍，内奸；痣；（医）胎块，肿瘤；墨西哥辣酱；防波堤，海堤港；（化）摩尔

Researchers studied moles on those aged between 12 and 50.
研究者们研究了12岁到50岁的人身上长的痣。