sconce / skäns/ • n. 1. a candle holder, or a holder of another light source, that is attached to a wall with an ornamental bracket.2. a flaming torch or candle secured in such a holder.ORIGIN: late Middle English (originally denoting a portable lantern with a screen to protect the flame): shortening of Old French esconse ‘lantern,’ or from medieval Latin sconsa, from Latin absconsa (laterna) ‘dark (lantern)’, literally ‘hidden (lantern)’ (i.e., a lantern with a device for concealing the light), from abscondere ‘to hide.’sconce² • n. archaic a small fort or earthwork defending a ford, pass, or castle gate. ∎  a shelter or screen serving as protection from fire or the weather.

sconce.
1. Earthwork or fort, especially in front of a gate or the main defences.

2. Protective screen or shelter.

3. Screen in the sense of a partition, e.g. to define a chapel, etc.

4. Squinch (see dome), in the sense of a small arch across the angle of a square room carrying a superimposed mass (e.g. in a church-tower carrying an octagonal spire).

5. Decorative lamp-bracket attached to a wall.

6. Seat or bench fixed in a screen-wall near a fireplace.

sconce1 lantern or screened candlestick carried by a handle XIV; bracket-candlestick XV. Aphetic — OF. esconse (i) hiding-place, (ii) lantern; or — medL. sconsa, aphetic of absconsa, sb. use of fem. pp. of L. abscondere hide.

sconce4 (Univ. sl.) fine in a tankard of ale, etc., e.g. for breach of discipline or convention. XVII. perh. a joc. ref. to SCONCE2.
Hence sb. XVII.

sconce3 (fortif.) small fort or earthwork. XVI. — Du. schans, †schantze brushwood, screen of brushwood for soldiers, earthwork of gabions — (M)HG. schanze, of unkn. orig.