You have an additional proficiency in a weapon that is not necessarily learned by your class. This may simply be a weapon your class may not generally care for, or even something one may not even normally consider a weapon, such as a log, chair, rubber chicken, etc...

Select one "weapon". When using this "weapon", you gain +1 damage to any rolls made with it.

Usually, the weapon has a special ability as well. Work with your DM to determine the ability should it have one. They do not necessarily need to be combat related, although they generally tend to be.

Some examples of abilities:

• Alive: The weapon is alive. It may be able to speak and influence things, as well as make an additional attack when used.
• Reach: A swing of the sword fires an invisible shockwave that can knock fliers from the air or stun them unless they make a successful DEX save.
• That's a Weapon?: Immediately after a successful use of your weapon, gain advantage on Intimidation checks against any creature who hasn't previously seen the weapon used.
• Screaming for Blood: The weapon never stops screaming. Ever. Disadvantage on any Stealth checks, but advantage on any Intimidation checks.
• Random Ricochet: Whenever this weapon fires a projectile that hits a nonliving object, flip a coin. Heads will ricochet and hit an enemy for full damage. Tails ricochets the projectile back at the user, dealing 1/4 damage.