1. of, relating to, or containing cobalt, especially in the divalent state (Co²⁺)
Usage: chemistry; technical

Examples

• Cobaltous chloride is used as a humidity indicator in desiccants.
• The cobaltous ion gives a pink color to solutions.
• Cobaltous compounds are important in industrial catalysis.
• The chemist prepared a cobaltous salt for the experiment.
• Cobaltous oxide is a black powder used in pigments.