Delfin means "dolphin" in some languages, and sometimes the term may be seen translated as "dolphin" even in proper names. The term may refer to one of the following.
- The Delfin (submarine), Russian submarine from 1900s
- The Delfin (commando), Russian submarine commando unit rumoured to be created 1970 for the purpose of attacking NATO harbours
- The Greek submarine Delfin
- The Aero L-29 Delfin, a military trainer aircraft manufactured in Czechoslovakia.
- Delfin Lend Lease are an Australian residential property developer
- Delfin Quishpe, the Ecuadorian singer
- Victor Delfín, the Peruvian sculptor