Purpose – This editorial seeks to examine the definition of a “digital library” to see whether one can be constructed that usefully distinguishes a digital library from other types of electronic resources. Design/methodology/approach – The primary methodology compares definitions from multiple settings, including formal institutional settings, working definitions from articles, and a synthesis created in a seminar at Humboldt University in Berlin. Findings – At this point, digital libraries are evolving too fast for any lasting definition. Definitions that users readily understand are too broad and imprecise, and definitions with more technical precision quickly grow too obscure for common use. Originality/value – A functional definition...