'Drying oil' definitions:

Definition of 'drying oil'

(from WordNet)
noun
An oil that hardens in air due to oxidation and is often used as a paint or varnish base

Definition of 'Drying oil'

From: GCIDE
  • Drying \Dry"ing\, a.
  • 1. Adapted or tending to exhaust moisture; as, a drying wind or day; a drying room. [1913 Webster]
  • 2. Having the quality of rapidly becoming dry. [1913 Webster]
  • Drying oil, an oil which, either naturally or after boiling with oxide of lead, absorbs oxygen from the air and dries up rapidly. Drying oils are used as the bases of many paints and varnishes. [1913 Webster]