脑筋急转弯可以用 "brainteaser" 来表示。这个词源于英文 "brain" 和 "tease"。"brain" 指的是大脑，而 "tease" 意为挑战或逗乐。所以 "brainteaser" 就指挑战大脑的问题或难题。

例句：

I love solving brainteasers because they make me feel smart.

Can you help me with this brainteaser? I can't figure it out.

My uncle always tells the best brainteasers at family gatherings.