黑線 [－线]

Jyutping hak1 sin3
Pinyin hēi xiàn

Definitions (Wiktionary)
  1. noun, Internet, neologism
    the vertical lines in the emoji -_-||||| which conveys a sense of helplessness, cheerlessness, awkwardness, etc.
  2. noun, literally
    black line; black string
  3. noun, figuratively
    black line (used during the Cultural Revolution to refer to things counterrevolutionary)
Definitions (Kaifangcidian)
  1. （沒有對應漢語詞彙）