The word "Heroess" is an incorrect spelling of "heroine", which is the feminine form of "hero". The correct spelling is "heroine" with a long "i" sound /ˈhɛrəʊɪn/ at the end. The incorrect spelling may have been influenced by the plural form of "hero", which is "heroes". However, adding an extra "s" to "heroine" creates an unnecessary and confusing spelling. It is important to use correct spelling to ensure clear communication in writing.
The word "Heroess" is not found in dictionaries or commonly used in English. It appears to be a combination of the word "hero" and a suffix "-ess", which is traditionally used to form feminine forms of nouns. In this case, "heroess" could be speculated to refer to a female hero, but it is not grammatically correct or widely recognized.