Fehlstelle

Fehlstelle is a German term used to denote a place where something is missing or defective. The word derives from fehl, meaning missing or faulty, and Stelle, meaning place or position. In neutral usage, a Fehlstelle is any gap, vacancy, or defect in a material, a document, or a process where something expected to be present is absent.

In the natural sciences and engineering, Fehlstelle is frequently used to describe a point defect in a crystal lattice. A vacancy (Löcher) is a lattice site that is present in the ideal structure but unoccupied. Such defects affect diffusion, electronic structure, and mechanical properties. The broader notion can also include interstitial defects, dislocations, or other irregularities that create localized discontinuities in an otherwise regular arrangement.

In other contexts, Fehlstelle denotes a gap or missing element in a plan, an argument, data, or text. It can describe a data point that was not recorded, a missing word in a manuscript, or a weak point in a system or procedure. The term is often used to emphasize the identification of a defect location rather than the defect itself.

Synonyms and related terms include Leerstelle and Lücke. The word Fehlstelle is used across technical and everyday language to point to a specific location of absence or defect within a larger whole.