STD is a three letter acronym standing for sexually transmitted disease. STD may also refer to:

Standards or Standardization

Standard deviation, a statistical measure

Saves the Day, an American punk rock/emo/indie music band

Severe Tire Damage (album) (1998), an album by They Might Be Giants

State transition diagram, a graphical representation of a state transition for a finite state machine

Internet standard, a specification for an innovative internetworking technology or methodology

Severe Tire Damage (band), a rock and roll "garage" band from Palo Alto, California

São Tomé and Príncipe dobra, the ISO 4217 code for the currency of São Tomé and Príncipe

The Scottish Football League Third Division

Doctor of Sacred Theology, (Sacrae Theologiae Doctor)

Subscriber trunk dialling, or subscriber toll dialling, the standard codes for telephone dialing in India, the United Kingdom and the Republic of Ireland