From the Oxford
English Dictionary entry for pennon:
3.3 The long pointed streamer of a ship; also called pendant and pennant.
1627 Drayton Agincourt lxvii, A ship most neatly that was lim'd, In all her Sailes with
flags and Pennons trim'd. [In Chalmers's Poets, pennants, whence in Richardson.] ***
1632 Sherwood, A Penon (or Pendant) in a ship. ***
1658 Phillips, Penon,‥also a streamer in a ship. ***
1807 J. Barlow Columb. ii. 354 O hapless day!‥That saw my wandering pennon mount the tide. ***
1852 Longfellow Warden of Cinque
Ports ii, Flowing flag and rippling pennon. ***
1884 Mrs. C. Praed Zéro xiv, Yachts with pennons flying lay at
anchor in the harbour.