a feeling of being annoyed, upset, insecure, or dissatisfied due to unfulfilled needs, things not achieved, or things which cannot be changed or resolved;
e.g. I was experiencing great frustration at my inability to play the musical piece correctly.
(noun)
something that causes one to feel annoyed or upset at something that they cannot change or resolve;
e.g. She didn't know how to handle his frustration if he didn't help her.
(noun)
the action of preventing something by stopping it from progressing or being completed/successful;
e.g. He was involved with the frustration of their attempts.