The CiteKey (labeled "Access Phrase" in versions of Citation previous to 8.2) is a unique identifier for each record in a datafile. You can insert a CiteKey or Access Phrase as a key in your paper to cite a work in your Citation datafile.

The field for a CiteKey is in all the Citation forms:

To cite Dickson’s book in a paper, enclose the Access Phrase in curly braces:

The derivation of the word occupy has attracted the attention of several researchers into the fundaments of the English epistemological and linguistic experience {Dickson 1982}.

When included in a document to cite a bibliographic work, a CiteKey is called an Access Key. See the topic on Access Keys for more details on Access Keys in documents.