PSD

PSD can stand for:__NOTOC__

Politics

* Social Democratic Party, a political party of Portugal
* Social Democratic Party, a political party of Romania
* Social Democratic Party, a political party of Benin
* Socialist Destourian Party, the old name (to 1988) of the ruling party in Tunisia, currently called Constitutional Democratic Rally
* Civil Movement "People's Self-Defense", a political movement in Ukraine and part of the Our Ukraine–People's Self-Defense Bloc electoral alliance

Financial Services

* Payment Services Directive, an initiative to regulate payment services and payment service providers in the European Union

Travel

* IATA code for Port Said Airport, Port Said, Egypt

ciences

* PSD, discrete controller (Proportional/Sum/Derivative) - a version of PID controller (Proportional/Integral/Derivative) - PID controller
* Particle size distribution
* Phase sensitive detector
* Position sensitive device or position sensitive detector, a device that measures the one- or two-dimensional position of a lightspot
* Positive-semidefiniteness as it relates to matrices
* Postsynaptic density, a specialization of the cytoskeleton at the synaptic junction
* Post-source decay, a technique used in MALDI mass spectrometry
* Power spectral density, the power of a signal per some unit of measurement such as temporal or spatial frequency used in signal analysis
* Prevention of significant deterioration, an American environmental program created under the Clean Air Act designed to maintain existing air quality in areas already meeting EPA National Ambient Air Quality Standards

Computers

*.psd (Photoshop document), the default file extension of the proprietary file format of Adobe System's Photoshop program.
* A portable or personal storage device, small hard disks designed to copy digital photographs from a camera
* Programmable system device, an integrated circuit manufactured by ST Microelectronics and including Flash-ROM, RAM, and logic functions on a single chip
* Program structure diagram, also known as a Nassi-Shneiderman diagram
* Power supply disturbance, a fault model for embedded systems and system-on-chip devices

Medicine

* Post-traumatic stress disorder (more commonly abbreviated PTSD)

People

*PSD (rapper), a rapper from the Bay Area

Others

* PES Stats Database, a forum dedicated to the Pro Evolution Soccer series with a compiled list of player's "stats"
* Protective Services Detail, U.S. Army unit assigned to protect VIPs
* Personal Security Detail, a group of private security contractors tasked with protecting a client
* Pesticides Safety Directorate, UK
* Philippine School Doha, a Filipino school in Doha, Qatar
* Platform screen doors, doors used on the edges of underground railway platforms
* Power Split Device, part of the Hybrid Synergy Drive on a Toyota Prius
* Program Service Data, also known as "program-associated data", usually data sent along with an HD radio program
* Psychiatric service dog, a specific type of assistance dog that helps people with psychiatric disabilities
* Punch Sport Drink, a drink served to midshipmen at the United States Naval Academy
* Ford Power Stroke engine, the Ford turbo diesel engine available in the F250 / F350 line as well as other trucks
* Pewter Soap Dish, a dish made out of pewter meant to hold bars of soap