While pinning down a definition has proven tricky, the general consensus is it's some means of information gathering.

虽然事实证明给好奇下定义很难，但大家普遍认为它是一种收集信息的手段。

youdao

Pinning down exactly what it is that makesHan Han so famous can be difficult.

要搞清楚韩寒究竟为什么这么出名可能是困难的。

youdao

Empirically, economists have long had trouble pinning down the wealth effect from housing.

从经验上看，经济学家们一直以来都难以说清楚房产财富效应。

youdao

Never get so wrapped up in pinning down particulars that you kill the novel for yourself.

FORBES: Five Links For NaNoWriMo Inspiration

But pinning down such dietary links is no easy task according to Dr Knight.

ECONOMIST: Disease

The Taliban were able to use their higher positions to fire into the base, pinning down the troops.

CNN: Afghan insurgents pushed into U.S. base, official says