ineffable

1. ADJ You use ineffable to say that something is so great or extreme that it cannot be described in words. 不可言喻的[正式] [usu ADJ n]

...the ineffable sadness of many of the portraits. ...许多肖像流露出的不可言喻的悲伤。

2. ineffablyADV [usu ADV adj]

...his ineffably powerful brain. ...他那无法形容的超强智慧。