Which dress code should i put?

My wedding is 4 months away and I've recently had a lot of people ask me what they should wear. I didn't think I had to provide this information because most people have been to weddings and other formal events before. I decided I have to put it on the website, but I'm not sure which language is best: cocktail, semi-formal, or something else.
It is not black tie. Long or short dresses, jumpsuits, or suits are all fine as long as it looks dressed up. I was thinking "semi-formal," but I read somewhere that semi-formal is the same as business casual/dressy casual and our event would be a step or two up from that. So not sure what to say?