Sentence:  A line of fifty <WSD>trucks</WSD> from the Zenith Steel and Machinery Company was attacked by strikers-rushing out from the sidewalk, pulling drivers from the seats, smashing carburetors and commutators, while telephone girls cheered from the walk, and small boys heaved bricks. 
Meaning of the word marked with <WSD> tags:  A semi-tractor ("semi") trailer;  a lorry.