- Abbreviation of standard definition TV. A digital format which has video and audio quality equal to or exceeding NTSC, but below that of HDTV. There are multiple SDTV standards, each having differences in frames per second and lines of resolution, providing either a 4:3 or 16:9 aspect ratio, while surround sound may or may not be supported.
- acronym forStandard Definition television
- acronym forStandard Definition TV