硬膠 [－胶]

Jyutping ngaang6 gaau1
Pinyin yìng jiāo

Definitions (粵典–words.hk)
  1. 形容詞、粗俗
    戇​鳩​嘅​諧​音
    stupid; near homophone of, and euphemism for 戇鳩(ngong6 gau1); literally: hard plastic
  2. 近義詞
    膠
  3. 名詞
    硬度​高​嘅​塑​膠​，​例如​阿​加力​膠
    plastic with high hardness, eg PMMA
Definitions (Wiktionary)
  1. noun
    hard rubber; ebonite

硬膠 [－－]

Jyutping ngaang6 gaau1
Pinyin yìng háo

Definitions (CC-CANTO)
  1. rigid plastic; euphemism for 'dumbass'