'Driftage' definitions:

Definition of 'driftage'

(from WordNet)
noun
The deviation (by a vessel or aircraft) from its intended course due to drifting

Definition of 'Driftage'

From: GCIDE
  • Driftage \Drift"age\, n.
  • 1. Deviation from a ship's course due to leeway. [1913 Webster]
  • 2. Anything that drifts. [1913 Webster]