bulla
bul.la \'bu.l-*\ \'bu.l-.e-, -.i-\ \'bu.l-.a-t\ n or bul.lae [ML] [NL, fr. L] pl 1: the round usu. lead seal attached to a papal bull 2: a hollow thin-walled rounded bony prominence 3: a large vesicle or blister - bul.late aj
Webster's English Dictionarybul.la \'bu.l-*\ \'bu.l-.e-, -.i-\ \'bu.l-.a-t\ n or bul.lae [ML] [NL, fr. L] pl 1: the round usu. lead seal attached to a papal bull 2: a hollow thin-walled rounded bony prominence 3: a large vesicle or blister - bul.late aj