a miser; a cheapskate; someone stingy with money or generosity (colloquial).
彼は友達の前でもけちんぼうで、いつも割り勘にこだわる。
He's stingy even with friends and always insists on splitting the bill.
そんなにけちんぼう呼ばわりしないでよ。必要なときは払うから。
Don't call me such a cheapskate. I'll pay when it's necessary.
あのキャラクターはけちんぼうで笑いを取っている。
That character gets laughs by being portrayed as stingy.