Whilst this may appear to be a potential case of defamation (this includes libel if it is in written form, or slander if it is in oral form), such claims are rather difficult to pursue. Many people are keen on suing for defamation without having full appreciation of the law or practicalities in doing so. I will try and clarify the position below.
First of all, certain conditions must be met for the statement to be classified as defamatory. These are:
1. There has to be a defamatory statement - the assessment that is often used to establish this is whether the statement tends to lower the claimant in the estimation of right-thinking members of society generally
2. Its publication has caused or is likely to cause serious harm to the reputation of the claimant – this will vary based on what effect it will have but it really has to be something sufficiently serious
3. The statement has been published by the defendant to a third party
4. The claimant must prove that the words complained of were published about him - this should not be an issue if the claimant is named or clearly identified.
Whilst it may be easy to prove that defamation has taken place, the legal process of pursuing such a claim is often complex and prohibitively expensive. A claim must be made in the High Court and will likely require the help of professional defamation lawyers, so the costs will often be high right from the outset, usually in the thousands. There is also no legal aid available for such claims so the complainant must fund these personally.
You must also consider whether the publisher of the statement can potentially defend the claim. For example, this can happen by proving the statement was true or an honest opinion which could have been made based on the available facts.
Instead of starting legal proceedings it would be best to contact the publisher of the comment, advise them that what they have done amounts to defamation and that you will consider pursuing the matter further if they do not retract their statement and issue an apology. This could prompt them to reconsider their position, which would avoid the need for court action. Of course, if they refuse to comply the option of suing still exists, but consider the above information before going down that route.
An alternative is to argue that this is harassment, as long as it has occurred on more than one occasion and that is something which can be reported to the police or you can pursue it in the civil courts as well.
Does this answer your query?