This is the 14529th most frequent Russian word.
парламентская
Parliamentary.
The word "парламентская" is used as an adjective describing the 'system' (система) as being related to a parliament.
Парламентская система правления существует в нескольких странах.
The parliamentary system of governance exists in several countries.
Here, "парламентская" qualifies the 'newspaper' (газета) as being associated with a parliament or parliamentary affairs.
Парламентская газета публикует новости о политике.
The parliamentary newspaper publishes political news.
In this sentence, "парламентской" describes the 'delegation' (делегация), indicating its relation to a parliament.