Are these terms actually interchangable? I could easily be wrong but in my mind they are two different things. I think someone on here once pointed out that not every slave is a sub and not every sub is a slave if that makes sense at all. I consider myself a sub rather than a slave and my Mistress has always refered to me as a sub or a puppy. I would think a slave would be 24/7, 365 while a sub may be only in certain aspects like the bedroom or when they are with their dominate one. Feel free to correct or add additional info. Thanks in advance.