Sentence:  Also <WSD>three</WSD> other direct pathways of alveolar bronchial arterial supply were noted : via the pleura ; through the interlobular septa ; and along the terminal bronchiole ( figs. 14 , 17 , 18 , 19 ) . 
Meaning of the word marked with <WSD> tags:  the cardinal number that is the sum of one and one and one