ENGLISH
REFERENCE

semi

n. countable
B2 Upper Intermediate US //ˈsɛmaɪ// UK //sˈɛmi// se·mi Informal Slang

n. a very large truck that carries goods across long distances. It is made of two parts: the engine part where the driver sits and a long trailer behind it.

n. an articulated vehicle consisting of a tractor unit and a semi-trailer. Primarily North American in usage; the term is a clipping of 'semi-trailer truck'.


SIMPLE

A large semi blocked the narrow road.

CONTEXTUAL

The logistics company purchased ten new semis to handle the increased demand for cross-country shipping.

COMPLEX

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.

Synonyms
Origin

The prefix semi- (from Latin) used as a noun.

Usage

Commonly used in North American English; British English speakers typically use 'lorry' or 'articulated lorry'.

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