I hate going somewhere , I never know what to wear!! What is lounge wear?

[lisad123]

Seriously!! I have a very important event this week, few famous people in a very famous place and invite says "lounge wear" seriously??
Last time we went to house of lords it said something similar and struggled to find suitable stuff.
Dh says he will just go in his suit, but I'm stuck.
What would you class as lounge wear for a woman?

I would wear a smart dress or top and trousers with heels.

Black dress

Debretts says:

"...The equivalent for women is a skirt or trouser suit, cocktail dress or evening gown depending on the time of day and the occasion."

Is it evening or day?

Day, I would wear this dress worn with a tan belt & this jacket and tan (NOT NUDE!) heels. Cream or red bag.

Evening? I would wear a black cocktail type dress.

www.dresscodeguide.com/default.asp?Dresscode=6&Local=1&Climate=2&TimeOfDay=3&Gender=1&Reload=1&MoreCodes=&AutoRun=1

Its 6-8pm so early evening. Thanks for help