# semi

/ˈsɛmaɪ/ (US) · /sˈɛmi/ (UK)

Source: https://englishreference.com/word/semi
Updated: 2026-06-19

## Senses

### 1. a house

noun · CEFR B1 · British English · Informal

a house that is joined to another house on one side.

For teachers: a semi-detached house, sharing one common wall with an adjacent property.

- They live in a quiet semi at the end of the street.
- The developer converted the Victorian semi into two separate apartments, though the shared wall required significant soundproofing.

Usage: Commonly used in British and Australian English to describe residential property.

### 2. a large truck

noun · CEFR B1 · American English · Informal

a very large truck used for carrying goods over long distances.

For teachers: a semi-trailer or tractor-trailer used for heavy haulage.

- The highway was full of semis carrying supplies to the city.
- The driver struggled to manoeuvre the semi through the narrow industrial estate, eventually requiring a spotter to assist with the tight turn.

Usage: Primarily North American usage; the British equivalent is 'artic'.

### 3. sports match

noun · CEFR B1 · Informal

a match or race that comes just before the final.

For teachers: a semi-final round in a knockout competition.

- Our team won the semi and will play for the trophy on Sunday.
- After a gruelling semi that went into extra time, the players had only three days to recover before the championship match.

### 4. finance/tech

noun · CEFR C1 · Informal · Technical

companies that make computer chips.

For teachers: shorthand for semiconductor companies or their stocks.

- Investors are buying semis because of the high demand for AI chips.
- The portfolio manager increased exposure to the semis, betting that the supply chain constraints would ease by the third quarter.

### 5. firearms

noun · CEFR C1 · Slang

a gun that fires one bullet each time you pull the trigger.

For teachers: a semiautomatic firearm.

- The police found a semi hidden in the back of the car.
- The legislation specifically targets the sale of high-capacity semis to unlicensed individuals.

### 6. partly

adverb · CEFR B2 · Informal

partly or somewhat.

For teachers: to some extent; partially.

- I was only semi-conscious when the alarm went off this morning.
- The project was only semi-successful, as it met the technical requirements but failed to gain traction with the target audience.

Usage: Usually functions as a prefix, but used as a standalone adverb in very casual speech.

## Examples

- A large semi blocked the narrow road.
- The logistics company purchased ten new semis to handle the increased demand for cross-country shipping.
- Driving a semi requires specialized training and a commercial license, as the weight and length of the vehicle significantly increase braking distances and complicate tight turns.

---

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.