There are lots of different slang terms for things in this world. In every genre or culture there are certain terms and slang used that are only understood by a select few. I noticed a few in the fanfiction community. Below is a short list of terms that I thought were quite steady in TF fanfiction. :)
Fic --> aka fiction or fanfiction. This word has taken on the form of a noun to replace the word story. All tend to use this slang in the TF universe.
Disclaimer --> Most of the webpages have these on them. They are proclaimations that the author is writing for entertainment only, not for a profit. If you sell your fanfiction your are in copyright infringements of the creators of the Transformers or any other company that owns the rights to the characters, ideas etc. Hasbro, the main creators of TF, encourage people to write, that it's okay to use their characters. They just don't want them to be sold. It's ILLEGAL. As long as the author attaches a disclaimer there's no problem. To most authors it is second nature to begin each fic by saying "so and so are my creations and my copyrights. All other TF/BW characters are the sole copyrights of Hasbro, Alliance, Mainframe etc. No profit is intended, for entertainment only." Other than that major rule, fanfiction has none.
TF- Transformers
G1- Generation One
BW- Beast Wars
BM- Beast Machines
TF:TM-Transformers: The Movie