NPC naming is one of the means through which the DM can communicate the relative importance of the character to the plot. An NPC who is even a minor player in the plot will typically be given a "normal" (for race, class, and geography) name. An NPC who is a one-off, or throw away, will be given a name following the Buckaroo Bonzai rules.
The alien antagonists in the movie The Adventures of Buckaroo Bonzai Across the 8th Dimension followed the pattern of first name John followed by a last name, typically a nonsense last name such as Smallberries or Yaya. An NPC who is not important to the plot shall follow this convention, with examples such as:
A modified form shall be used for elvish or fey names - fake Greek names. For example, "Tricycles" would be pronounced "Tri'-Sik-Lees", and "Diagonal" would be "Dia Go'nal". These names will keep the proper mystery of the fey.