at a loss アット・ア・ロス (慣用句等) 途方にくれて, 当惑して Idiom: at a loss 1. Below cost: eg. sold the merchandise at a loss. 2. Perplexed; puzzled: eg. I am at a loss to understand those remarks.

ballsy 威勢のいい, 心臓の強い balls・y 形容詞[悪い俗語] Very tough and courageous, often recklessly or presumptuously so.