Mandatory – required by law, compulsory
(Pronounced man-duh-tree)
To remember the definition of the word mandatory, use the following mnemonic:
The man tore the tree down (mandatory): he had to do it because it was compulsory when a tree exceeded the height limit.
Examples of mandatory in a sentence
Primary school attendance is mandatory in all countries.
She could not log in to her account because she was unable to complete all mandatory fields.
Crash helmets are mandatory for motorcyclists in the U.K.