Cid

Cid may refer to:
 * Cid (soil)
 * Cubic inch (c.i.d., cid), a displacement unit for internal combustion engines
 * Cid, a slang term for lysergic acid diethylamide (LSD)
 * Content-ID, a URI scheme (cid:) that allows the use of MIME within email

People

 * El Cid (1043–1099), 11th-century Castilian nobleman
 * Cid Corman (1924–2004), poet
 * Cid Samson (born 1943), Canadian politician
 * Gérald Cid (born 1983), footballer
 * Hilda Cid (born 1933), Chilean scientist
 * Mauro Cid (born 1979), Brazilian military

Fictional characters

 * Cid (Final Fantasy), character in Final Fantasy video games
 * Cid the Dummy, the main protagonist of his eponymous video game
 * Cid Scaleback, Trandoshan informant in the 2021 animated series Star Wars: The Bad Batch
 * Cid Kagenou (シド・カゲノー) (known as Minoru Kageno (影野実) before reincarnation) from the light novel, manga and anime The Eminence in Shadow