English Reference
noun

helmet

n.
US /ˈhɛɫmət/ UK /hˈɛlmɪt/ hel·met UK spelling helmet's, helmet's, helmeting

  1. 01 A2 Elementary

    a hard hat you wear to protect your head from injury.

    a piece of protective equipment worn on the head to prevent injury from impact, falling objects, or accidents.

    Simple

    You must wear a helmet whenever you ride your bicycle on the road.

    In context

    Safety regulations require all personnel to wear a reinforced helmet while present on the construction site to mitigate the risk of head injuries.

    hard hatheadgear
  2. 02 C2 Proficiency Technical Science

    a part of a plant or animal that looks like a hard hat.

    a structure in certain plants or animals that resembles a protective head covering in shape or function.

    Simple

    The flower has a small helmet that protects the seeds inside.

    In context

    The upper sepal of the monkshood flower forms a distinct helmet, which serves to protect the reproductive organs from heavy rain.

  3. 03 C2 Proficiency British EnglishSlangVulgar

    a rude word for the end of a penis.

    a vulgar slang term referring to the glans penis.

    Simple

    The comedian made a crude joke about a helmet that made the audience uncomfortable.

    In context

    The script was edited for television to remove several instances of 'helmet' used as a vulgar anatomical reference.

Head down, Delves’s teardrop-shaped helmet is steady as his legs whir round for the sprint stages.

The Guardian· 18 Aug 2026

And the union's president Adam Hansen told BBC Sport there needs to be better helmet safety as cyclists hit record-breaking speeds during races.

BBC News· 15 Aug 2026

From Middle English helmet, helmett, a borrowing from Old French helmet, heaumet, a diminutive of helme (Modern French heaume), equivalent to helm + -et. The Old French is itself of Germanic origin (whence Old English helm). Used in English since the 15th century, it has largely displaced helm as the general word.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin gem -
Level B2 · Upper Intermediate
Frequency Common
Updated