spinal tap
noun/ˈspaɪnl tæp/
/ˈspaɪnl tæp/
[countable] (North American English) (also lumbar puncture [countable, uncountable] British and North American English)
(medical)- a medical procedure in which liquid is removed from the lower part of the spine with a hollow needle, usually in order to diagnose a medical problem (= identify what it is)
腰椎穿刺（放液）