linseed oil

a yellowish oil extracted from flaxseeds that is used in drying paint, ink, etc.

Linseed oil is a type of oil made from the seeds of the flax plant. It is commonly used as a mixing substance in oil paints to improve their flow and drying time. Linseed oil helps paint stick to surfaces and can improve the paint's durability and shine. It is also used in wood finishing and as an ingredient in varnishes and other coatings.