A social or romantic engagement at an arranged time and place.
Season 6, Episode 1 - The Date Night Variable
Aired September 27, 2012
Amy is not impressed when Sheldon invites a lonely Raj along on their date night. Penny and Leonard's romantic evening together also gets interrupted after Amy sends Raj away. Meanwhile, Howard and his mother are caught in an argument, even as he's 220 miles above earth in the International Space Station.
Season 9, Episode 8 - The Mystery Date Observation
Aired November 12, 2015
Sheldon, Wolowitz and Koothrappali post an online advertisement to find Sheldon a new girlfriend. Also, when Amy is coy with details about a guy she is dating, Penny and Bernadette decide to spy.