Meaning of “trial” - Learner’s Dictionary

trial

noun [ C, U ] us uk /traɪəl/
This trial has gripped the whole nation.The trial has been seriously compromised by sensational media coverage.The court notified her that her trial date had been postponed.The suspect remained locked up while awaiting trial.A trial must be fair and impartial.
LAW

B2 a legal process to decide if someone is guilty of a crime:

The two men are now on trial for attempted murder.
He will be taken to the US to stand trial.
TEST

a test of something new to find out if it is safe, works correctly, etc:

trial and error

a way of learning the best way to do something by trying different methods:

There aren't any instructions with it - it's just a matter of trial and error.

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