Not being a smarty pants or anything but I beg to differ on the spaghetti straps. The maxi dress was invented in the 70's, most of them had long sleeves. From my understanding a maxi dress tends to be fitted in the bust area and flows down to the ground.

Here's a defintion I found...

Maxi dress
From Wikipedia, the free encyclopedia

A Maxidress is a floor or ankle length informal dress. Maxidresses are formfitting at the top and loose flowing at the bottom, cut to flow over the body. Usually made out of cotton or polyester. They come in a variety of necklines, colors and patterns.

Also maxi dresses can come in many colours and patterns
A maxi dress is ... something you can't wear if you're 5'1" like me as they're just TOO long!!!!!
I can't wear them either Leasha...and 3/4 pants are full length on me too.