a.

1. 不切題的，不中肯的[（+to）]
   His impertinent remarks wasted valuable time.

   他那些不著邊際的話浪費了寶貴的時間。

2. 不恰當的；不合理的
   impertinent curiosity

   過分的好奇心

3. 傲慢的；不禮貌的；莽撞的
   It was impertinent of him to behave like that.

   他那種舉止很不禮貌。

adj.

1. not showing proper respect.
2. formal not pertinent.