- SPD (Shimano Pedaling Dynamics)
- SPDE (Solid Phase Dynamic Extraction)
- SPDF (Orbits in an electron shell)
- SPDIF (Sony Philips Digital Interface Format)
- SPDN (Social Pedagogy Development Network)
- SPDP (Superintendents Professional Development Program)
- SPDR (Seattle Purebred Dog Rescue)
- SPDT (Single Pole, Double Throw)
- SPDT — (i) Single (Pole Double-Throw)
- SPDU (Session Protocol Data Unit)
- SPE (Society of Petroleum Engineers)
- SPEAK (Suicide Prevention Education Awareness For Kids)
- Spealer. (Specialiter ("Specially"))
- SPEAN (Spectral Analysis)
- SPEAR (Self Preservation Encouraging Active Response)
- SPEC (Specification)
- SPECAT (SPECial CATegory)
- SPECC (Space-Enhanced Command and Control)
- SPECIAL (Strength, Perception, Endurance, Charisma, Intelligence, Agility, and Luck)
- SPEC.POP. (Special Population Students)
- SPECS (SDL Performance Evaluation of Concurrent Systems)
- SPECT (Single-photon-emission computerized tomography)
- SPECTRA (Sportsmanship, Participation, Excellence, Character, Teamwork, Respect, and Achievement)
- SPECTRE (Special Executive for Counterintelligence, Terrorism, Revenge and Extortion)
- SPECTRE — SPecial Executive for Counter (intelligence, Terrorism, Revenge and Extortion)
- SPECWAR (Special Warfare)
- SPED (Special Education)
- SPEE (Superficial punctate epithelial erosions)