A list or table of the explanations for symbols, characters, terms, or abbreviations, where each entry in the list names a symbol (or similar) and provides a gloss for that symbol. Such lists act as a key to the symbology of a graphic, figure, or table.
The following, in order:
<editing-instruction> Editing Instruction, zero or more
<label> Label of a Figure, Reference, Etc., zero or one
Any combination of: