Abbreviation Meaning
Activity + # Request for # number of players to join in on an activity. (E.g. Raids +2)
+1 A single item that can be preserved by the Protect Item prayer in a PvP situation
2H Two-handed weapon
3a Third Age
4t, 4taa, 4 tick, c4t Four tick auto attack or the patched "constant 4taa"
99 The maximum level for 24 of the 27 skills
120 The maximum level for Dungeoneering, Invention, and Slayer. The maximum virtual level cap for all skills, besides Invention, which has a maximum cap of 150.