She was delirious with happiness after receiving the admission letter.

delirious 是形容词，由名词 delirium（谵妄、极度兴奋）加上形容词后缀 -ous 构成。原指因发烧或精神错乱导致的意识模糊状态，引申为"极度兴奋、狂喜"的状态，常用来形容因强烈情绪而失去理智控制的样子。