helmet
/ˈhɛlmət/noun
A strong covering worn on the head for protection, historically part of a soldier's armor.
Example sentence
- “Always wear a helmet when you ride your bike.”
The standard verb is 'wear', and safety writing uses 'helmet laws' and 'helmet use'. Bike, motorcycle, football, and combat helmets are all just 'helmets'; English does not subdivide the word.