a mark used to indicate the word above it should be repeated
"The teacher wrote her name on the list and then drew a ditto mark next to every other student's entry so they could all sign their names."
That which was stated before, the aforesaid, the above, the same, likewise.
"When asked if he wanted extra toppings on his pizza and the salad bar order too, I just nodded and said ditto."
To repeat the aforesaid, the earlier action etc.
"When asked what toppings she wanted on her pizza, I simply replied ditto to my friend's order of pepperoni and mushrooms."
As said before, likewise.
"I love pizza, and I say ditto for pasta too."
Used as an expression of agreement with what another person has said, or to indicate that what they have said equally applies to the person being addressed.
"That's exactly how I feel about the new policy; ditto."