a glycoprotein (= a type of protein that contains a carbohydrate group) that forms a structure that sticks out on the outer edge of a virus, which helps the virus to attach itself to a cell in a person's or animal's body and enter the cell

Members of the coronavirus family have sharp bumps known as spike proteins that protrude from the surface of their outer envelopes. 冠状病毒科的成员在外壳蛋白表面上有尖锐的突起，被称为刺突蛋白。

The emergence of SARS was probably linked to the adaptation of spike protein to bind strongly to human cells. SARS的出现可能与刺突蛋白结构发生调整使之与人类细胞结合能力加强相关。