Swearing-in pledge (4)

I believe the answer is:

oath

(Other definitions for oath that I've seen before include "Curse or solemn promise" , "bad language" , "Vow; profanity" , "One sworn" , "Vow or expletive" .)

I've seen this clue in the Newsday.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.