An existential clause is a clause, having a distinctive grammatical structure, which expresses the real or imagined existence of an entity.
An existential clause often introduces an entity into a discourse.
(English)
The clause construction "there + verb [typically be] + noun phrase" forms an existential clause, as in:
This page is an extract from the LinguaLinks Library. Version 5.0 published on CD-ROM by SIL International, 2003.