delete function in javascript code example

Example 1: what is the function of delete operator in javascript

var student= {age:20, batch:"ABC"};
delete student.age;

Example 2: delete js

let monTableauAssociatif = {
     'prenom' : 'Mark' ,
     'nom'    : 'Zuckerberg' , 
     'poste'  : 'Pdg de Facebook',

 } ;
 delete(monTableauAssociatif.poste)
 console.log(monTableauAssociatif) ;