D defs.my
Entry 2 senses Webster, 1913

Cid

/sĭd/ · IPA /sɪd/
01 n. Chief or commander; in Spanish literature, a title of Ruy Diaz, Count of Bivar, a champion of Christianity and of the old Spanish royalty, …
  1. 1.
    Chief or commander; in Spanish literature, a title of Ruy Diaz, Count of Bivar, a champion of Christianity and of the old Spanish royalty, in the 11th century.
  2. 2.
    An epic poem, which celebrates the exploits of the Spanish national hero, Ruy Diaz.