As has been noticed by several people, the Drydock v2 beta includes several weapon traits that aren't currently included in the Unity rulebook. Some of them are from the Star Fleet Universe (SFU) conversions; others are truly "new" but not yet implemented. Here is a quick guide:

Power Points (1PP/2PP/3PP/4PP) - The weapon requires a number of Power Points (PP) to fire. This is a SFU-only trait.

Accurate (Acr) - The existing Pinpoint trait is being renamed as this.

Armor Penetrating (AP) - The weapon ignores screens (soon to be renamed "Armor").

Evaporating (Evp) - Applied only to a Seeker weapon, this trait causes the flight to lose one Seeker at the end of every turn until it is gone. Used to reflect Plasma Torpedoes in the SFU.

Multi-Shot Expendable (Exp2/Exp3/Exp4) - The weapon can be fired a limited number of times; e.g. Exp3 means the weapon can be fired three times before being used up. The existing Expendable trait is the same as "Exp1".

Fighter-Exclusive (FtX) - The weapon can only be fired at tiny targets; it is too weak to have an effect on starships.

Pinpoint (Pnp) - The weapon is able to selectively target enemy systems. Each damage die that comes up 4-6 can be rerolled: 1-2 = Engines; 3-4 = Weapons; 5-6 = Shields.

Piercing {special} (Pr+) - This is used for the upcoming Full Thrust conversion.

Semi-Armor Penetrating (SAP) - The weapon applies half damage (rounded up) to the target's screens (soon to be renamed "Armor"); the rest goes through to the ship.

Shield-Killer (ShK) - This is a SFU-only trait.

Seeker (Skr) - Used to indicate the weapon is a Seeker.

Multi-Turn Slow (Slw2/Slw3) - The weapon can only be fired every third or every fourth turn (i.e. it must be inactive for either two or three turns).

Starship Exclusive (SsX) - The weapon can only be fired at starships; it is too big and/or imprecise to fire at tiny targets.