noun
a person who learns another's role in order to be able to act as a replacement if needed
verb
to study or learn (a role or part) as an understudy
-
The understudy stepped in when the lead actor fell ill.
-
The understudy had to fill in for the main actor at the last minute.
-
The understudy had to pinch-hit for the star performer.
-
Being the understudy in life means always being prepared to take on unexpected challenges.