Nostril/ˈnɑːstrəl/ Definition 1 of 1Pro Tip 1/3Physical Descriptions Use 'nostril' when describing someone's nose for details or if they're flaring their nostrils. When he got angry, his nostrils flared noticeably. Pro Tip 2/3Blocked Nostrils Mention 'nostrils' to discuss breathing difficulties, like when having a cold. With her nostrils blocked, she struggled to breathe clearly. Pro Tip 3/3Animal Descriptions Animals have nostrils too, useful in descriptions for biology or storytelling. The horse's wide nostrils flared as it galloped around the track.