a.

1. 不會老的
   His face was smooth and ageless.

   他的臉光潔，不顯老。

2. 永遠的，永恆的
   The origin of the universe is an ageless topic.

   關於宇宙的起源的問題是個永恆的論題。

adj.

1. not ageing or appearing to age.
2. lasting a long time or forever:
   ageless Taoist massage techniques.