adverb
hurriedly; in a hurry; hastily
Describes acting quickly due to sudden necessity or urgency, often with a nuance of rushing.
急遽、会議を開くことになった。
We had to hold a meeting hurriedly.
彼は急遽
He returned to his country in a hurry.
na-adjective
Obsolete adjectival use; modern Japanese prefers 突然 or 急な for 'sudden'.
古い文書では「急遽な出来事」のような表現が見られる。
In old documents, expressions like 'a sudden event' can be found.