1. (chemistry) the theory that all indicators are either weak acids or weak bases in which the colour of the ionized form is different from the colour before dissociation
   - Ostwald's theory of indicators

Type of: scientific theory

• lustre
• lustreless
• lustrelessness
• lustreware
• lustring
• lustrous
• lustrously
• lustrum
• lusty
• lusus naturae
• Lut Desert
• Luta
• lutanist
• lute
• luteal
• luteal phase
• lutecium
• lutefisk
• lutein
• luteinizing hormone
• lutenist
• luteotropin
• luteous
• lutetium
• lutfisk