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Hard plastic 「硬膠」

Vulgar

Used in Hong Kong

derived from the cantonese words "on gau/on9" which sound similiar to hard plastic in cantonese.

Pronunciation: "on-gau" ("on" in English, "9" in Cantonese)

Meaning: stupid, pointless, idiocy ,lame, foolish
Stop being so Hard plastic !!!!
(stop being so foolish)

Person A is hard plastic
(person A is stupid)
by HKslang2011 June 15, 2011