The CoE recognises that consistent use of terminology is key, and states:
``In this recommendation the following terms are used with the following meanings: [...]''
The terms that it chooses to define are: authentication, ballot, candidate, casting of the vote, e-election or e-referendum, electronic ballot box, e-voting, remote e-voting, sealing, vote, voter, voting channel, voting options and voter's registrar.
However, even in this short set of ``definitions'', fundamental terms are used inconsistently. For example, the voter's register is not defined as a list of voters, it is defined as a list of persons entitled to vote (electors). Consequently, in some instances, later in the document, the term elector is used inconsistently to refer to a voter; which may lead to confusion between a person who is entitled to vote and a person who actually does vote. Another potential problem arises because the term `vote' can be used inconsistently as both a verb and a noun. This can lead us to two different, yet reasonable, interpretations of some of the standards.
A different type of inconsistency arises when undefined terms are used in the definitions and these terms appear to be inconsistently used. For example, the ``casting of a vote'' definition refers to the ballot box. Only ``electronic ballot box'' is defined and its definition does not refer to a ``ballot box''. However ``ballot'' is defined. Thus, in the standards, the term ``ballot box'' can be interpreted as being ``electronic'' or otherwise when the difference between them is not made explicit.
The definitions that the CoE provide demonstrate that they realised that consistent use of terminology is important. However, they also suggest that they did not get adequate expert advice as to how these definitions would have been handled during analysis and requirements capture of an e-voting system. Surprisingly, one of the most common expressions in the standards is that of ``e-voting system'', yet ``system'' is never defined!
To conclude, the poor specification of the fundamental concepts actually increases the likelihood of internal inconsistency in the standards document. A quick reading of the other standards instruments shows the same inconsistent use of terminology and so it is also unlikely that the standards document will be externally consistent with these other documents.