A condensed formula is a written formula in which most bonds are omitted and the atoms are grouped immediately after the carbon to which they are attached, for example CH3CH2CH2COOH. It matters as a compact way to convey connectivity in a single line of text without drawing the structure. It is briefer than a displayed formula, which shows every atom and every bond explicitly, but it conveys less of the molecule's shape.

缩简式是一种书写式,其中大部分键被省略,各原子紧接在所连接的碳之后成组书写,例如 CH3CH2CH2COOH。它的意义在于能用一行文字简洁地表达连接关系而无需画出结构。它比展开式更简短(展开式会明确画出每一个原子和每一根键),但表达分子形状的信息较少。