Meaning

• To join or unite (e.g. one thing to another, or as several particulars) so as to increase the number, augment the quantity or enlarge the magnitude, or so as to form into one aggregate.

• To sum up; to put together mentally.

  "to add numbers"

• To combine elements of (something) into one quantity.

  "to add a column of numbers"

• To give by way of increased possession (to someone); to bestow (on).

• To append (e,g, a statement); to say further information.

• To make an addition; to augment; to increase.

  "It adds to our anxiety."

• To perform the arithmetical operation of addition.

  "He adds rapidly."

• To summon minions or reinforcements.

  "Typically, a hostile mob will add whenever it's within the aggro radius of a player."