Webster's Revised Unabridged Dictionary · 1913

Ditto

Ditto , noun

[Italian, detto, ditto, from Latin dictum. See Dictum.]

The aforesaid thing; the same (as before). Often contracted to do., or to two “turned commas” (”), or small marks. Used in bills, books of account, tables of names, etc., to save repetition.
A spacious table in the center, and a variety of smaller dittos in the corners. — Dickens

Ditto , adverb

As before, or aforesaid; in the same manner; also.