noun, plural rec·tri·ces [rek-trahy-seez, rek-truh-seez] /rɛkˈtraɪ siz, ˈrɛk trəˌsiz/. Ornithology.
- one of the tail feathers of a bird controlling direction during flight.
noun plural rectrices (ˈrɛktrɪˌsiːz, rɛkˈtraɪsiːz)
- any of the large stiff feathers of a bird’s tail, used in controlling the direction of flight