錙銖 [锱铢]

Jyutping zi1 zyu1
Pinyin zī zhū

Definitions (Wiktionary)
  1. noun, literally, literary
    zi (¹⁄₄ of a tael) and zhu (¹⁄₂₄ of a tael), both are small weight measures in ancient China
  2. noun, figuratively, literary
    a tiny amount; a very small amount
  3. noun, figuratively, literary
    a small profit; a very small amount of money
Examples (粵典–words.hk)
  1. Cantonese
    锱铢必较
    錙銖必較
    • fight over the smallest trifles