VOQ (Voice of Quellious, level 65 group buff - a higher version of KEI. Gives more mana regen and higher buff bonuses but lasts a shorter time).
KEI (Koadic's Excellent Intellect. Buffs mana regen, INT, WIS and Manapool)
VQ (Vallon's Quickening. Group buff, buffs haste, ATK, Dex and Agi.)
SOV (Speed of Vallon, single target version of VQ)
FOS or FO7 or Seventh (Focus of Seventh, highest shaman group buff. Buffs HP, Dex and Strength. Doesn't stack with Cleric self buff line Armor of the Risen etc)
FOSO (Focus of Soul. Single target version of above)
Harnessing of Spirit - Level 49 version of the Focus line.
9 or BOTN (Blessing of the Nine. Highest Druid group buff. Buffs HP, AC and Mana regen. Doesn't stack with Cleric self buff line, Paladin self buff Aura of the Crusader or the Cleric Resolution and Virtue lines)
9 or POTN (Protection of the Nine. Single version of above)
POTG (Protection of the Glades. Lower level version of the above)
[b]HOV (Hand of Virtue. Highest cleric group buff. Buffs HP and AC. Doesn't stack with Druid buff BOTN line.)
Virtue (single version of HOV)
BOA (Blessing of Aegolism. Lower version of HOV)
Aego (Aegolism. Single target BOA)
Temp (Temperance. Lower level version of HOV/Aego. Can be cast on characters of levels <46)
There's a ton of other buffs, of course, but these are the ones that I see people trying to auction most often. Note that abbreviations and acronyms tend to differ from server to server, so YMMV.