What's the difference between boyar and boyau?

Boyar

Definition:

• (n.) Alt. of Boyard

Example Sentences:

• (1) It is leaving it – without all hell breaking lose between rival boyars, and with his personal fortune intact.

Boyau

Definition:

• (n.) A winding or zigzag trench forming a path or communication from one siegework to another, to a magazine, etc.

Example Sentences: