based on profession dicriminated

Casual comments by the ignorant can not amount to discrimination in legal terms, and it only shows ignorance.  You can retaliate by stating such examples of why teaching is the noblest profession in building a powerful nation, as the person that made such comments came up to that level only through teachers only.

These potentially defamatory statements may harm a teacher's professional reputation and significantly hamper your ability to perform effectively in the classroom. A legal remedy available to teachers in such cases is to initiate a defamation case against the defamer.  

To succeed in a slander defamatory (where the statement is Oral)  action, a teacher would require to show that the defamation discredited her character or professional reputation and can recover damages. If the slanderous statement did not harm the teacher's professional reputation, however, special damages would have to be proven before any recovery would be allowed

Section 499 to 502 of IPC talks about criminal defamation and the Law of torts talks about civil defamation.

Some of the essentials of defamation include-

• The intention of the person defaming must be to lower the reputation of the person against whom the statement is made. 
• Defamation must be published- Made known to a party other than the person defamed.
• The statement must refer to the plaintiff
• In a civil defamation case-  Plaintiff can move either to the High Court or to the subordinate courts and seek damages in the form of monetary compensation from the accused.

In a criminal defamation case, a guilty person can be sent to jail for two years as per sections 499 and 500 of the Indian Penal Code, 1860.

Every citizen of the country has the right to live with dignity. Mental Harassment or emotional or physical abuse is a punishable offense. 

Yes, an action is possible. But how will adduce evidence to prove the allegations.

It is best that such uninformed persons are left to themselves.

If you are so concerned, serve a legal notice.