helmet
//ˈhɛlmɪt//
Noun
helmetSingular
helmetsPlural
1
A protective covering for the head, typically made of hard material, worn by soldiers, motorcyclists, cyclists, construction workers, and others to protect against injury.
You must wear a helmet when riding a bicycle.
2
A piece of armor covering the head, especially one worn by medieval knights.
The knight put on his helmet before the battle.