Sentence:  The <WSD>pulmonary</WSD> vein , however , without the limiting supportive tissue septa as in type 1 , , follows a more direct path to the hilum and does not maintain this close relationship ( figs. 8 , 22 ) . 
Meaning of the word marked with <WSD> tags:  any of four veins that carry arterial blood from the lungs to the left atrium of the heart