If you gesticulate, you make movements with your arms or hands, often while you are describing something that is difficult to express in words.
例句
A man with a paper hat upon his head was gesticulating wildly...一個戴紙帽的男子在拼命地打手勢。The architect was gesticulating at a hole in the ground.那位建筑師在指著地上的一個洞打手勢。