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 Moreira (1927-2024), Brazilian news anchor
- Cid Samson (born 1943), Canadian politician
- Gérald Cid (born 1983), footballer
- Hilda Cid (born 1933), Chilean scientist
- Mauro Cid (born 1979), Brazilian military
- Sofía Cid (born 1971), Chilean politician
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
See also
- CID (disambiguation)
- El Cid (disambiguation)
- Sid (disambiguation)