A Member of Parliament who does not have cabinet rank, and who therefore sits on one of the backbenches or in one of the back rows of the legislature.(noun)
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Use "backbencher" in a sentence
"She's a first-term backbencher from exurban Minneapolis who says the Lord told her to run for Congress."
"He's called a backbencher because anytime someone on these pages says anything nice or positive about a Republican it must be tempered with a slap."
"If he was an abject failure or what Mark Levin calls a backbencher, nobody would give Rush a second look."