Meaning of “rusty” - Learner’s Dictionary

rusty

adjective uk us /ˈrʌsti/
METAL

B2 Rusty metal has rust (= an orange substance) on its surface:

rusty nails
SKILL

B2 If a skill you had is now rusty, it is not now good because you have forgotten it:

My French is a bit rusty.

(Definition of “rusty” from the Cambridge Learner’s Dictionary © Cambridge University Press)