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

• assumption
• Assumption of Mary
• assumptive
• Assur
• assurance
• Assurbanipal
• assure
• assured
• assuredly
• assuredness
• assurgent
• assuring
• Assyria
• Assyrian
• Assyrian Akkadian
• Assyrian Neo-Aramaic
• Assyriology
• Astacidae
• Astacura
• Astacus
• Astaire
• Astana
• Astarte
• astasia
• astatic