She had worked as a call centre operator making cold calls for time-share vacations.

她曾经在一个呼叫中心担任话务员，打陌生推销电话推销分时度假。

《柯林斯英汉双解大词典》

Unsolicited means "not asked for." so cold calling is the skill of making a sales call to someone who is not expecting you.

unsolicited的意思是“不是别人主动要求的”，所以打“无约电话”也就是给那些不期望接你电话的人打销售电话。

youdao

Does hearing the phone ring make you panic? Doesthe thought of making a call give you cold sweats?

听到电话铃声响起的时候，你有没有感到很恐慌？一想到要给别人打电话，你是不是就会冒出一身冷汗？

youdao

For that call, I received a polite cold shoulder from the other panelists who were making those year-end predictions.

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