Baseboard

Baseboard - Finish trim where the floor and walls meet.
Base Molding - The decorative wooden strip along the top edge of the baseboard.

baseboard (skirting board) - interior finish trim hiding the wall and floor junction
bay - sections of a building, usually counted by windows and doors dividing the house vertically [related to massing] ...

baseboard, mopboard, skirting board - a molding covering the joint formed by a wall and the floor
astragal, beading, beadwork, bead - a beaded molding for edging or decorating furniture ...

Baseboard
Is generally a wooden board covering the lowest part of an interior wall. Its purpose is to cover the joint between the wall surface (usually plaster or drywall) and the floor. It covers the inevitable uneven edge as flooring meets the wall.

dado Paneling, usually wood, that is applied to the lower portion of a wall, above a baseboard.
dais A raised platform in a room for dignified occupancy; the high table, historically at the end of a dining hall.

Trim - The finish materials to a building, such as moldings applied around openings (window trim, door trim) or at the floor and ceiling of rooms (baseboard, cornice, picture molding).

Backer board - Gypsum baseboard
Backfall - A slope in a gutter (or any gravity drain) that is opposite to the intended direction of flow, resulting in pounding or backflow ...

quarter-round or baseboard trim) is normally applied where walls meet floors. Within a flight of stairs there is no trim as the trim thickness will significantly eat into the tread width.

See also: Floor, Finish, Door, Architecture, Ornament