Billy: So what did you get?
Jennifer: It's all in the bag.
Billy: What's this? Essential oil? Wow! This stuff is expensive.
Jennifer: I need that to relax. I'm going to put a few drops in my bath water.
Billy: How is oil supposed to make you relax?
Jennifer: They all have essence of flowers in them.
Billy: [Opening the little bottles] Mmmm. They smell nice.

essential oil (n.) 　
精油。essential是「精华的，精粹的」，名词是essence

比 利：那你买了什么？
珍妮花：全在袋子里。
比 利：这是啥啊？油精？哇！这玩意儿可贵了。
珍妮花：我需要它来帮我放松。我要在我的洗澡水里加上几滴。
比 利：油要怎么帮你放松？
珍妮花：它们里头都有花香精华。
比 利：（打开小瓶子）嗯。很好闻。