1. (

• trial_and_error

) experimenting until a solution is found ;

1. (

• trial-and-error

) trying out various means or theories until error is satisfactorily reduced or eliminated; "he argued that all learning is a trial-and-error process that resembles biological evolution" ;

2. (

• trial-and-error

) relating to solving problems by experience rather than theory; "they adopted a trial-and-error procedure" ;