Related Clues:

• Promised
• Insisted
• Blasphemed
• Talked like a sailor, stereotypically
• Risked getting bleeped
• Risked an FCC fine
• Talked X-ratedly?
• Gave one's word, pledged
• Took oath or cursed
• Uttered profanities or avowed
• The cursed South had this on
• Dim prose may be expected from this
• Said some bad words
• Declared under oath
• Affirmed solemnly