Not sure of a 3, but a 4 would be "Hlwn"
You stand out if respect, just like that of the national anthem. Imagine if everyone sat down, it would seem like they "don't care." Once again just respect, and you would also take off your hat if you're wearing one.
i think it may be "oct" i am looking for this same answer for my crossword and i have the "c" and the "t" but couldn't decide on the first letter. Hope that helps!
Jellyfish (costume OBVIOUSLY!!)