a.

1. 喧闹的，嘈杂的
   a noisy crowd

   喧闹的人群

2. 充满噪声的，吵吵嚷嚷的
   The streets were as noisy as ever.

   街上和往常一样喧闹。

3. （颜色，服装等）过分鲜艳的；（文体）过分渲染的
   He wore a noisy sweater.

   他穿了件颜色十分鲜艳的毛衣。

adj.

1. full of or making a lot of noise.
2. technical accompanied by random fluctuations that obscure information.