'Solid' is term for a partner one has been romantically involved with for a long period of time and is not married to. This term is appropriate for couples to use when most people would expect them to be married and better conveys commitment over use of 'girlfriend' or 'boyfriend'.

hot, sexy.. good looking

THIS BEING IS NIETHER HUMAN NOR HERMIT, HE IS A SOLTOISE.
This small retiring creature spends alot of its energy playing with choke.
on the DEcoy living room floor he enjoys such delicacies as cookies(or crack to the averge tort) and cucumbers. beware this beast is fearsum, he'll have your eye out perry!

A friend who is not your best friend, however they are really close to you. You don't necessarily need to chill with them all the time like you would a best friend. You can even go weeks with out talking to them, but when you do chill its like you've never been apart. A solid will be there for you no mater what. They're a friend who can last a life time as apposed to a best friend, where your friendship could crumble over the years. Its just having a true genuine friend.

someone who thinks themsleves hard

When some thing is really hard to do!

adj. originated as slang during the 80's meaning "cool" or "good" brought back to life in a small Pennsylvanian town