Sentence:  The higher classes see the unions, the strikes, the May Day Celebrations, and feel the calamity that is threatening them, and their terror passes into an instinct of self-defense and hatred. They know that if for one instant they are <WSD>worsted</WSD> in the struggle with their oppressed slaves, they will perish, because the slaves are exasperated and their exasperation is growing more intense with every day of oppression. 
Meaning of the word marked with <WSD> tags:  To outdo or defeat, especially in battle.