Meaning:

The term “主打” translates to “the main feature,” while “一个” literally means “one” but carries no specific meaning in this context, serving instead to emphasize content that follows. This phrase is commonly used by streamers on short video platforms like Douyin, intended for humorous effects to indicate that “the main feature of something or someone is…” For instance, grown-up children who reside with their parents and lack independent income may jokingly claim that their main feature is “being good company and comfort” for their parents.

Example:

A: 你弟弟为什么特别受女生欢迎？

Nǐ dìdi wèishénme tèbié shòu nǚshēng huānyíng？

Why is your younger brother so popular with girls?

B: 因为他主打一个幽默。

Yīnwèi tā zhǔdǎ yīge yōumò。

Because his primary attribute is his sense of humor.