ISO 4378-4:2009定义了滑动轴承领域使用的基本符号。附加符号也被定义为上标和下标。 使用的字符来自拉丁和希腊字母、阿拉伯数字和其他符号，例如点、逗号、水平线或星号。在最简单的情况下，应用程序符号仅由基本字符组成；在最复杂的情况下，指带有下标和上标（附加符号）的基本字符。出于国际适用性的目的，所有基本符号和附加符号均源自英语单词，并尽可能采用迄今为止技术文献中使用的名称。 已尝试对所有类型的滑动轴承的符号进行广泛的一致性。 该分类用于计算、技术和几何测定，以及滑动轴承的质量保证。

ISO 4378-4:2009 defines basic symbols for use in the field of plain bearings. Additional signs are also defined for use as superscripts and subscripts. The characters employed are drawn from the Latin and Greek alphabets, Arabic numerals and other signs, for example points, commas, horizontal lines or asterisks. In the simplest case, an application symbol consists of the basic character alone; in the most complex, of the basic character with subscripts and superscripts (additional signs). For the purposes of international applicability, all basic symbols and additional signs have been derived from English words, and designations used in technical literature up to now have been adopted as far as possible. Wide conformity of the symbols for all types of plain bearings has been attempted. This classification is established for use in calculations and technological and geometrical determinations, as well as in the quality assurance of plain bearings.