da·do 
(dādō)
(dādō)n. pl. da·does
1. Architecture The section of a pedestal between base and cornice.
2. The lower portion of the wall of a room that is decorated differently from the upper section, as with panels.
3.
a. A rectangular groove cut into a board so that a like piece may be fitted into it.
b. The groove so cut.
tr.v. da·doed, da·do·ing, da·does
1. To furnish with a dado.
2.
a. To cut a dado in.
b. To fit into a dado.
[Italian, gaming die, cubical block, dado, from Old Italian, die, possibly from Latin datum, given, neuter past participle of dare, to give; see DIE2.]