n.

1. （現只用於at random）任意行動；隨機過程[U]
   He took a book at random.

   他隨手取了一本書。

a.

1. 胡亂的；隨便的，任意的
   He was not listening and made a random answer to the teacher's question.

   他不在聽講，對教師的問題瞎答一通。

2. （建築材料等）大小不一的，規格不一的
3. 【統】隨機的
   random sampling

   隨機取樣

4. 【物】無規則的

adj.

1. made, done, or happening without method or conscious decision.
   ▸Brit. informal rather strange; odd.
2. Statistics  governed by or involving equal chances for each item.
3. (of masonry) with stones of irregular size and shape.