Delete a specific term or facet mapping from lucene main index which refers to categories in taxonomy

[Chitra R]

Hi,
    I am using Lucene 4.10.4. Is there any way to delete a term or
facetfield mapping from lucene main index which is used to refer the
categories in taxonomy. And i know once a category is added to the
taxonomy, it can never be deleted. So i am trying to remove that facet map
from main index.

Thanks in advance.

Regards,
Chitra