záo sǐ mǎo zi
variant of 鑿死鉚子|凿死铆子[zao2 si3 mao3 zi5]
凿
záo
(bound form) chisel
死
sǐ
to die
卯
mǎo
old variant of 卯[mao3]
子
zi
noun suffix, as in 椅子[yi3 zi5] "chair"