noun
lacking the words to express oneself; having a poor vocabulary
Slang term for struggling to find the right words, often used self-deprecatingly or humorously.
ボキャ貧だから、うまく説明できない。
I can't explain it well because I'm lacking the right words.
彼はボキャ貧で、いつも同じ言葉ばかり使う。
He has a poor vocabulary and always uses the same words.