I completely respect the fact that "no" absolutely means no in non-BDSM contexts, but since my sub and I occasionally do resistance play (bordering on consensual non-consent at times), "no" just doesn't work for us. I understand "only saying no when you damn well mean it," but even in non-resistance scenarios, my sub will occasionally blurt out a "no!" (in the same way that she might yell "ow!" after an unexpectedly hard spank). However, if we haven't explicitly discussed doing resistance play for a particular session and I hear a string of repeated "no"s, I'll slow down and check in just to make sure (after all, it's not impossible for someone to forget a safe word).

I think No can be your safe word if you establish it with your partner first. I understand what others are saying by No shouldn't be the safe word and it makes sense for them. However, if you have talked to your partner and said NO means NO, so NO is my safe word. Then it's a pretty good word to pick. Personally, no is my safe word. No means NO and if I have things going on that I don't want; the first thing I am going to say is NO! So, to me it's a great safe word. But if you have the type of relationship were no doesn't mean no, then I would pick something else.

'No' is not a safeword for me. A big part of why I go into d/s scenes is to explore very dark, personal territory and that includes graphic language, crying, and repeatedly saying 'no'.
If you are in a safe playspace, this needs to be discussed. This is the only ONLY time that 'no' doesn't mean No (only after careful negotiation, and only during a scene).

I'll chime in again, I recommend the stoplight safewords. Check in with your partner periodically, with the words 'green' to continue, 'yellow' to pause/reframe and 'red' for an all out, immediate stop. If you are bound and unable to speak, holding up 1, 2 or 3 fingers for a specific amount of time (three pulses, five seconds, etc). Its important to be able to steer a scene if it starts to turn before you even have to hit the eject button. Having to stop a scene is a failure of communication on both partner's sides; a medium-level safeword can help prevent that from happening.

I think that NO is too common of a word to use, and can be taken out of context to easily in the heat of the moment. I would use something very uncommon like Tube Socks or Spaghetti...something that would not be used at all in a sexual situation.

I think a safe word should be distinct and easily recognizable to ensure an almost instant stop to anything that's uncomfortable or potentially dangerous.

I don't think it makes a good word. It's to easy to say. But if that's the word that you want to use then it's your decision to use it.

"No" is a safeword if no other safeword has been established. If you plan on saying "no" or "stop" during a scene, be sure your partner knows you're not withdrawing consent. Talk about safewords first, and always be respectful of whoever you're with.

it shouldnt be

No should never be a safe word because its fun to say no and have the dom keep going.

For me it is certainly not a safeword, only because I have a habit of actually saying it during scenes when I am not in my head the word tends to come out of me when I am being pushed but its not a 'oh god this is too much or no I don't want this' kind of push. So we use something I would never ever say no matter what the context of the scene.

It is iffy territory, My sub is bratty she says no all the time, however as a dom I feel it's my job to know when No certainly does mean no. If you've crossed over the line badly you can't expect a person to remember their safe word.

It CAN be, but you should be careful that it's so commonly used in normal conversation. ("Did you do your chores today?" "No...") I don't have an official safeword because I don't often do play that needs one and my partner is very sensitive to my nonverbal cues, but most will respond to red and yellow.

I think it depends on your play and your dynamic.

Our safeword is always RED because its very commonly used and the only safeword used at the play parties we attend.

We do some consensual non-consent sometimes and no definitely does not mean no in those situations.

But its not for everybody.