A person who appears on a panel, either as a member of a committee or jury, or as part of a panel game.(noun)
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Use "panellist" in a sentence
"The TV panellist is comedian Russell Howard, he's funny."
"Freud had a famously varied career which included stints as a politician, chef, restaurateur, food writer, horse racing pundit, children's writer, and dog food advertiser, but he was perhaps best known as a panellist on"
"Later that year a panellist at the MediaGuardian Edinburgh International Television Festival claimed that coverage of Harry's tour of duty had been used by the Taliban as a propaganda tool for recruitment."