This is the 1802nd most frequent Japanese word.
国会
National Diet (Japan's legislative body).
Here, '国会' is used to refer to the National Diet, the legislative body where laws are debated and passed.
国会で重要な法案が議論されています。
An important bill is being discussed in the National Diet.
In this instance, '国会' is mentioned as a place that one can visit, highlighting its significance as the seat of legislative activity.
国会を訪れた学生たちは政治に興味を持ち始めました。
The students who visited the National Diet started to take interest in politics.
'国会' identifies the institution of legislation, from which '国会議員' derives, referring to members of this institution.