semitrailer

UK: /ˌsɛmɪˈtreɪlə/ US: /ˈsɛmɪˌtreɪlɚ/ ,(sem′i trā′lər)

WordReference Random House Learner's Dictionary of American English © 2025

sem•i•trail•er /ˈsɛmɪˌtreɪlɚ/   n. [countable]

1. Transport a trailer for hauling freight, with wheels at the rear end and the forward end supported by the back of the truck that pulls it.

Also called semi /ˈsɛmaɪ/ .

WordReference Random House Unabridged Dictionary of American English © 2025

sem•i•trail•er  (sem′i trā′lər), n. 

1. Transport Also called semi. a detachable trailer for hauling freight, with wheels at the rear end, the forward end being supported by the rear of a truck tractor when attached. Cf. full trailer. 
2. Transport tractor-trailer.

• semi- + trailer 1915–20

Collins Concise English Dictionary © HarperCollins Publishers::

semitrailer / ˌsɛmɪˈtreɪlə/ noun

1. a type of trailer or articulated lorry that has wheels only at the rear, the front end being supported by the towing vehicle