opaque type

基本解释

Unlike the other two, this is not an opaque type; its structure is documented.
与另外两个数据类型不同，这是一个透明的类型；其结构在文档中有介绍。
The binaryvar data type is a variable-length opaque type with a maximum length of 255 bytes.
binaryvar 数据类型是一种变长的 opaque 类型，最大长度为 255 字节。
Lacquerwork: Any of a variety of decorative objects or surfaces, usually of wood, to which a coloured, highly polished, and opaque type of varnish called lacquer has been applied.
漆器：表面涂有彩色、高度磨光的不透明漆的装饰性对象的统称，通常为木制。