HDRip stands for "High Definition Rip." It is a term often used in online video piracy to describe video that has been "ripped" from a high-definition television broadcast or another digital source. The term itself doesnt necessarily indicate the resolution of the ripped video, as HDTV broadcasts can vary in resolution. The "ripping" process involves copying the material digitally, either through a digital capture card recording the broadcasted TV show or by copying the material from a DVR device without copyright protection flags. This means that the original material is of good quality or near perfect. HDRips can be distributed as-is or compressed to another format or smaller resolution.
In summary, HDRip refers to a video that has been ripped from a high-definition source, but it does not specify the exact resolution of the video.
