Accidental gap
From a lexical gap is when in a ( natural ) language no word is available for a fact.
A classic example is the missing word for " no longer be thirsty " in German:
- No longer hungry = satisfied; no longer thirsty =?
The example shows a missing lexical symmetry of the German vocabulary. In part, the lack of symmetry as a lexical gap is specifically indicated.
Regardless of symmetry issues, it may also be missing, for example, in Archisemen to a lexical realization.
In the language development in children is called a stopgap strategy if lexical gaps are filled by a overgeneralization.