The word "seal" in Bengali is "মোহর" (mohor). It refers to a mark or stamp used for authentication, often made of wax or other materials.
Caste is a social hierarchy system based on birth, and it is not related to the word "seal" or its meaning in Bengali.
Perhaps you are thinking of a specific context where the word "seal" is used, and there is a related caste association. If you can provide more information about the context, I might be able to help you further.