helmet

noun

hel·​met ˈhel-mət 

1

: a covering or enclosing headpiece of ancient or medieval armor see armor illustration

2

: any of various protective head coverings usually made of a hard material to resist impact

3

: something resembling a helmet

helmeted

ˈhel-mə-təd 

adjective

helmetlike

ˈhel-mət-ˌlīk 

adjective

Examples of helmet in a Sentence

Recent Examples on the Web

Meanwhile, the thin, stretch material is lightweight enough to layer under a helmet if needed. —Alison Syrett Cleary, InStyle, 9 Jan. 2026

The first layer focuses on sound and vibration delivered through a helmet. —Aamir Khollam, Interesting Engineering, 9 Jan. 2026

But a helmet-less road trip to Alberta could just point to some reckless decision-making. —Maggie Fremont, Vulture, 9 Jan. 2026

Season 2 opens with a helmet-less Robby riding in on a motorcycle. —Senior Television, Los Angeles Times, 9 Jan. 2026

Word History

Etymology

Middle English, from Middle French, diminutive of helme helmet, of Germanic origin; akin to Old English helm helmet, Old High German helan to conceal — more at hell

First Known Use

15th century, in the meaning defined at sense 1

Phrases Containing helmet

• crash helmet
• pith helmet

Kids Definition

helmet

noun

hel·​met ˈhel-mət 

1

: a covering or enclosing headpiece of armor

2

: any of various protective head coverings usually made of a hard material

helmetlike

-ˌlīk 

adjective