wallboard (n.)

Old English weall, Anglian wall "rampart, dike, earthwork" (natural as well as man-made), "dam, cliff, rocky shore," also "defensive fortification around a city, side of a building," an Anglo-Frisian and Saxon borrowing (Old Saxon, Old Frisian, Middle Low German, Middle Dutch wal) from Latin vallum "wall, rampart, row or line of stakes," apparently a collective form of vallus "stake," from PIE *walso- "a post." Swedish vall, Danish val are from Low German.

Meaning "interior partition of a structure" is mid-13c. In this case, English uses one word where many languages have two, such as German Mauer "outer wall of a town, fortress, etc.," used also in reference to the former Berlin Wall, and wand "partition wall within a building" (compare the distinction, not always rigorously kept, in Italian muro/parete, Irish mur/fraig, Lithuanian mūras/siena, etc.). The Latin word for "defensive wall" was murus (see mural).

Anatomical use from late 14c. To give (someone) the wall "allow him or her to walk on the (cleaner) wall side of the pavement" is from 1530s. To turn (one's) face to the wall "prepare to die" is from 1570s. Phrase up the wall "angry, crazy" is from 1951; off the wall "unorthodox, unconventional" is recorded from 1966, American English student slang. To go over the wall "escape" (originally from prison) is from 1933. Wall-to-wall (adj.) recorded 1939, of shelving, etc.; metaphoric use (usually disparaging) is from 1967.

"piece of timber sawn flat and thin, longer than it is wide, wider than it is thick, narrower than a plank;" Old English bord "a plank, flat surface," from Proto-Germanic *burdam (source also of Old Norse borð "plank," Dutch bord "board," Gothic fotu-baurd "foot-stool," German Brett "plank"), perhaps from a PIE verb meaning "to cut." See also board (n.2), with which this is so confused as practically to form one word (if indeed they were not the same word all along).

In late Old English or early Middle English the sense was extended to include "table;" hence the transferred meaning "food" (early 14c.), as "that which is served upon a table," especially "daily meals provided at a place of lodging" (late 14c.). Compare boarder, boarding, and Old Norse borð, which also had a secondary sense of "table" and an extended sense "maintenance at table." Hence also above board "honest, open" (1610s; compare modern under the table "dishonest").

A further extension was to "table where council is held" (1570s), from whence the word was transferred to "leadership council, persons having the management of some public or private concern" (1610s), as in board of directors (1712).

"Bow to the board," said Bumble. Oliver brushed away two or three tears that were lingering in his eyes; and seeing no board but the table, fortunately bowed to that.

The meaning "table upon which public notices are written" is from mid-14c. The meaning "table upon which a game is played" is from late 14c. The sense of "thick, stiff paper" is from 1530s. Boards "stage of a theater" is from 1768.