The phrase "big applause" means a loud and enthusiastic clapping from a large group of people to show appreciation or approval for something. Full definition
The quality can't happen unless there's time set aside for quantity, too — big applause for you for being so on top of both of these critical factors. (renaissance.com)
Big applause for the content writer — he was true to my writing style, yet managed to convey the message in a professional, kind, and caring manner. (spotlightbranding.com)
Even more classy and drew big applause from the crowd was when he asked Wolverine creator Len Wein — who was sitting two rows in front of me in the reserved seating section — to stand up and wave his hand. (justpressplay.net)