Big party, need to state a dress code

[Calculuses]

It's a big celebration to mark a milestone for a club I belong to. We've got a beautiful venue and would like a dress code that means "made a bit of effort". Black tie would be too much and put off people who aren't accustomed to those kinds of dos though. It's in he evening in summer if that makes a difference. Fancy buffet and dancing.

What I'm envisaging is men in smart jeans or nice trousers with a their going out shirt and women in cocktail dresses or similar (I think women end of go more dressy anyway?)

Anyway, what's that called?

Smart casual, can specify a jacket no tie? Or just say no jeans?

cocktail

No trainers is probably what you want.

Smart casual I'd dress down for not up.

Lounge suits/cocktail would give me a good idea what you wanted. Dress to impress could be full ball gowns.

I don’t think smart casual is at all right. Cocktail is better.

Why can't people wear what they want? Does it matter if Janice turns up in jeans and trousers if that's what she feels happiest in? If it's to celebrate a hobby why can't people just wear what they feel happy with?

I would definitely go with "cocktail wear", implying smarter for men - ie smart trousers, shirt and dress or smart trousers for ladies

You have your expectations weirdly mismatched here. Men in smart jeans is not equivalent to women in cocktail dresses.

'Dress to impress' is the best suggestion.