concrete-head

The story

Purportedly from a calque from Japanese 頭(あたま)が固(かた)い (atama ga katai, “resistant to new ways of thinking”, literally “having a hard head”). Possibly originally from unattested Taiwanese Japanese *頭(あたま)コンクリート (atama konkurīto, literally “concrete-head”), which can be reconstructed from the phonetic borrowing of Taiwanese Mandarin 阿達馬孔固力／阿达马孔固力 (ādámǎ kǒnggùlì, “concrete-head”).