C1 adjective /ˌɪnɑːrˈtɪkjʊlət/
inarticulate
言葉が不明瞭
Meaning
Unable to express oneself clearly or effectively in speech or writing.
Example
She became inarticulate with emotion during the speech.
彼女はスピーチ中に感情で言葉が不明瞭になった。