hand waving

noun

1. insubstantial words, arguments, gestures, or actions used in an attempt to explain or persuade.

Example Sentences

Frustration then boiled over as animated hand waving was aimed the way of team-mate Rafael Leao late in the game.

From BBC

“Some people think that conducting is just a combination of hand waving and keeping the beat,” says Mr. Choi.

From NewsForKids.net

As the seconds go by, his apologetic demeanor morphs into something more like comedy — his head shaking, his hand waving in a vaguely Italian-style telegraph of exasperation, all of it coalescing into a fascinating improvisational bit.

From New York Times

For others, it was a skill to be honed and shown off at regular “showcases” that ballroom manager Ming Wei Ma, or Mr. Ma, excitedly pitched at the end of classes, his hand waving a flier in the air, DuVal said.

From Washington Post

“I remember her gloved hand waving back at me and was so impressed,” Paul, now 71, said.

From Seattle Times