HD is short for high definition. HD televisions and HD video make a picture with many tiny points of light, so faces and edges look clear and sharp — much clearer than old, fuzzy TV. People say “an HD TV” or “watch it in HD”. Though actually, shops and speakers stretch the letters: Full HD is a step up, and 4K is sharper still, so HD is no longer the newest “best picture”. It is everyday talk about screens, a little informal.

高畫質（台灣；中國大陸較常說「高清」）。口語也直接講 HD。