Adjective blackguardly has 1 sense
- rascally, roguish, scoundrelly, blackguardly - lacking principles or scruples; "the rascally rabble"; "the tyranny of a scoundrelly aristocracy" - W.M. Thackaray; "the captain was set adrift by his roguish crew"
Antonyms: honest, honorable (indirect, via dishonest)
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