A lightweight protective helmet, usually of metal or reinforced plastic, worn by workers in industrial Settings.

建筑工人戴的一种轻便的保护性(塑料或金属)头盔。

youdao

An internal head injury is usually more serious because the skull serves as the protective helmet for the delicate brain.

而闭合性损伤通常是更严重的，因为颅骨就像一个头盔一样，保护着我们精密的大脑。

youdao

Before he starts he must put on two sets of protective clothing, four pairs of gloves and a helmet with breathing apparatus, all of which is taped up so that not a particle of skin is exposed.

在他工作之前，他要穿上两套防护服，四双手套，一个带有呼吸系统的安全帽，这所有的一切都是为了把自己规整的实在，确保没有一丁点的皮肤暴露在外。

youdao

They quickly remedied this problem by finding a protective helmet for me to wear as I would run around.

CNN: 'I am an original young man'

Ranger Maguire, who was relaxing 0.6 miles (1km) away without his protective helmet and armour, fell within its range.

BBC: Ranger Michael Maguire

Hayden removed his protective helmet towards the end of his mammoth innings, preferring to don his beloved baggy green cap.

BBC: SPORT | Cricket | Lara lauds Hayden