1. substances used to dilute paint, varnish, or other liquids to make them less thick
Usage: plural form

Examples

• The painter added thinners to the oil-based paint to make it easier to apply.
• Always use thinners in a well-ventilated area due to the fumes.
• She bought some thinners at the hardware store for her art project.
• The label warned not to mix different types of thinners together.
• He cleaned his brushes with thinners after finishing the fence.
• The paint was too thick, so we needed to add more thinners.