What is fridgid?

my classmates always say things like fridgid...what is the meaning?

uhm for more of a school term when I was growing up that meant...SCARED TO BE SEXUALLY ACTIVE. im not saying thats the meaning in the dictionary biut when its being used in classrooms thats what it meant when I was growing up , and dont be offended if people are calling you that because TRUST me its a good thing, being a slut isnt cool ecspecially at a young age.

Its got two main meanings:
It can mean freezing cold temperature wise.
or it can be cold relating to personality.
Like when people are unresponsive.
Like when you say someone has a warm personality, it's the opposite with frigid.

Well..... actually the term "frigid" has been a hip-hop term that refers to diamonds. Like "icy" or "frozen" or "iced out". To say something is "frigid" could mean that it is either dripping with diamonds or that it merits wealth or "bling". Words like this start as one thing and start to expand on their encompassed meaning like "cool" which frigid could also be a derivitive of.

The other answers here are also very true, but I doubt that your classmates are referring to someone's sex drive or the general temperature. If someone says "that is frigid!" and it seems "cool" then you can probably go with my definition. If someone says "she is frigid" and it seems to be in regards to a relationship, go with the other definition.

Funguy above me said pretty much exatly what I was going to say!

frigid is never used in a good way... its like calling somone a prude ...