What does "rusty" mean?

Rusty: Impaired by inaction, disuse, or neglect. [Hector,] in this dull and long-continued truce, Is rusty grown. Shak.

Additional senses

  1. 2.Discolored and rancid; reasty; as, rusty bacon.
  2. 3.Surly; morose; crusty; sullen. [Obs. or Prov. Eng.] "Rusty words." Piers Plowman.
  3. 4.Rust-colored; dark. "Rusty blood." Spenser.
  4. 5.Discolored; stained; not cleanly kept; filthy. The rustly little schooners that bring fire wood from the Brititsh provinces. Hawthorne.
  5. 6.(Bot.) Resembling, or covered with a substance resembling, rust; affected with rust; rubiginous.

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