Definition

1. Noun:
   • A large freight trailer that has wheels only at its rear end, with its front end designed to be supported by a separate towing vehicle, typically a tractor unit or semi-truck.

Usage

• The primary use of the noun "semitrailer" is to refer to the trailer component of a tractor-trailer or articulated lorry combination. It is a specific type of trailer, distinct from a full trailer which has its own front axle.

Examples

• Noun:
  • The truck driver backed the semitrailer into the loading dock.
  • A fully loaded semitrailer can carry a significant amount of cargo.
  • The law requires all semitrailers to have working brake lights.

Advanced Usage

• "semitrailer" vs. "semi-truck": While often used loosely in casual speech, "semitrailer" technically refers only to the trailer portion. The entire vehicle combination is correctly called a "tractor-trailer," "articulated lorry," or colloquially a "semi" or "semi-truck."
  • Correct: The semitrailer was detached from the tractor for unloading.
  • Casual (but common): He drives a semi for a living. (This usually refers to the whole truck and trailer).

Variants and Related Words

• Semitrailer is the standard spelling. The hyphenated form semi-trailer is also common and acceptable.
• Trailer (n): A more general term for an unpowered vehicle towed by another.
• Tractor (n): The powered towing vehicle that connects to and supports the front of a semitrailer.
• Tractor-trailer (n): The complete combination of a tractor and a semitrailer.
• Articulated lorry (n): The British English term for a tractor-trailer.

Synonyms

• Trailer (in the specific context of freight transport, though this is a broader term).
• Semi (informal, short for semitrailer or the entire truck).
• Box trailer (if it has a fully enclosed box shape).

Antonyms

• Full trailer: A trailer that has both front and rear axles and is supported entirely on its own wheels when disconnected.

Noun

1. a trailer having wheels only in the rear; the front is supported by the towing vehicle