# Tri

/ˈtɹaɪ/ (US)

Source: https://englishreference.com/word/tri
Updated: 2026-08-15

## Senses

### 1. triathlon

noun · CEFR B1 · Informal

a short name for a triathlon, which is a race that includes swimming, cycling, and running.

For teachers: a colloquial clipping of 'triathlon', referring to a multi-stage competition involving three continuous and sequential endurance disciplines.

- He is training hard for his first sprint tri next month.
- After completing several local tris, she decided to register for a full-distance event to test her endurance limits.

Usage: Often used as a modifier before other nouns like 'bike' or 'suit'.

### 2. triceps muscle

noun · CEFR C1 · Informal · Slang

a short name for the triceps, the large muscle on the back of your upper arm.

For teachers: a colloquial clipping of 'triceps', specifically referring to the triceps brachii muscle in the context of bodybuilding or anatomy.

- You need to work on your tris if you want bigger arms.
- The athlete focused on isolation exercises to increase the definition in his tris and deltoids before the competition.

Teaching tip: This usage is almost exclusively found in gym culture and bodybuilding contexts.

## Examples

- I will try to finish my homework tonight.
- If the first method does not work, you should try a different approach to solve the problem.
- The legal team decided to try a new strategy during the appeal, hoping that the fresh evidence would finally sway the jury's opinion.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.