What does "Bloody oath" mean?
It means absolutely or a very definite yes. Bloody adds emphasis, making the reply sound enthusiastic or strongly in agreement.
The saying in a sentence
The saying
Bloody oath
Example
Bloody oath I'll be there.
When you use it
Use it with mates when you strongly agree or want to give an enthusiastic yes, such as accepting an invitation.
When you do not
Bloody is mild swearing, so avoid it in formal situations or around people who are uncomfortable with that language.