Light1  —n. 1 the natural agent (electromagnetic radiation) that stimulates sight and makes things visible. 2 the medium or condition of the space in which this is present (just enough light to see). 3 appearance of brightness (saw a distant light). 4 source of light, e.g. The sun, a lamp, fire, etc. 5 (often in pl.) Traffic-light. 6 a flame or spark serving to ignite. B device producing this. 7 aspect in which a thing is regarded (appeared in a new light). 8 a mental illumination. B spiritual illumination by divine truth. 9 vivacity etc. In a person's face, esp. In the eyes. 10 eminent person (leading light). 11 bright parts of a picture etc. 12 window or opening in a wall to let light in. —v. (past lit; past part. Lit or lighted) (attrib.) 1 set burning; begin to burn. 2 (often foll. By up) provide with light or lighting; make prominent by means of light. 3 show (a person) the way or surroundings with a light. 4 (usu. Foll. By up) (of the face or eyes) brighten with animation, pleasure, etc. —adj. 1 well provided with light; not dark. 2 (of a colour) pale (light blue; light-blue ribbon).  bring (or come) to light reveal or be revealed. In a good (or bad) light giving a favourable (or unfavourable) impression. In the light of taking account of. Light up 1 colloq. Begin to smoke a cigarette etc. 2 = sense 2 of v. 3 = sense 4 of v.  lightish adj. [old english]