It's probably the old naming system, where each expansion had it's own name for an AA upgrade to a previous expansion. This was changed after TSS sometime (TBS release, iirc) to the easier to follow 4 tab window (General, Archetype, Class, Special) and single names for the entire line of AAs.
If you can figure out or someone tells you what the LR stands for, you should be able to figure out which AA it is now. And if not from just the name, you should be able to find it listed online with it's description and figure it out from the description.
I've tried to include all the alternative names for AAs in the AA pages that I've been able to find, but I haven't put alot of effort into it, just ones, I knew, or got from searching old log files and such. See the bottom of http://everquest.allakhazam.com/wiki/EQ:Combat_Agility
page for an example.
And I agree, in general, you should always give the full name at least the first time you use an abbreviation, then you can use the abbreviation by itself throughout the rest of the document.
EDIT: After looking at Combat Agility, I see it used to be called Lightning Reflexes for ranks 4-8.
Yther Ore. Edited, Jan 31st 2013 10:39pm by Yther