Component. This is an item that is useful only when used in conjunction with an end item. Components are also commonly referred to as assemblies. For purposes of this definition an assembly and a component are the same. There are two types of components: Major components and minor components. A major component includes any assembled element which forms a portion of an end item without which the end item is inoperable. For example, for an automobile, components will include the engine, transmission, and battery. If you do not have all those items, the automobile will not function, or function as effectively. A minor component includes any assembled element of a major component. Components consist of parts. References in the CCL to components include both major components and minor components.
15 CFR § 772.1
The following are definitions of terms as used in the Export Administration Regulations (EAR). In this part, references to the EAR are references to 15 CFR chapter VII, subchapter C. Those terms in quotation marks refer to terms used on the Commerce Control List (CCL) (supplement no. 1 to part 774 of the EAR). Parenthetical references following the terms in quotation marks (i.e., (Cat 5)) refer to the CCL category in which that term is found. If a term is used in only one Export Control Classification Number (ECCN) on the CCL, then that term will not appear in this part, but will be defined in the Related Definitions paragraph in the List of Items Controlled Section of that ECCN.