Definition from Wiktionary, the free dictionary
blackguard (plural blackguards)
Usage notes 
- Usually, only used to refer to a male person.
- Blackguard may also refer to a man who uses foul language in front of a woman, typically a woman of high standing in society.
scoundrel — see scoundrel
See also 
- To revile or abuse in scurrilous language.
- (Can we find and add a quotation of Southey to this entry?)