lower house 
noun
1The larger of two sections of a bicameral parliament or similar legislature, typically with elected members and having the primary responsibility for legislation: the Bundestag or lower house of the German parliament...
- Under the German constitution, the Bundestag, the lower house of parliament, must be convened within a month of the election.
- Tasmania's got an electoral system where there's only 25 members of their lower house, the House of Assembly.
- Representatives to the lower house were elected by Puerto Ricans.
1.1 (the Lower House) (In the UK) the House of Commons.Until today when the vote on its progress was sent to the upper house after scraping through the lower house last week (I think)....
- This proposal is to be debated this autumn by the lower house, the House of Commons, as the next step towards it becoming law.