Sentence:  Suppoſe, thou Fortune could to tameneſs bring, // And clip or <WSD>pinion</WSD> her wing; // Suppoſe thou could'ſt on Fate ſo far prevail // As not to cut off thy Entail. 
Meaning of the word marked with <WSD> tags:  To cut off the pinion of a bird's wing, or otherwise disable or bind its wings, in order to prevent it from flying.