Fluff consists of soft threads or fibres in the form of small, light balls or lumps. For example, you can refer to the fur of a small animal as fluff.
The nest contained two chicks: just small grey balls of fluff.
窝里有两只小鸡:看上去还只是两个灰色的小毛球。
fluffs , fluffing , fluffed
If you fluff something that you are trying to do, you are unsuccessful or you do it badly.
She fluffed her interview at Harvard.
她把哈佛的面试搞糟了。