Merriam-Webster Collegiate Dictionary - flash

 I. verb  Etymology: Middle English flaschen, of imitative origin  Date: 13th century  intransitive verb  1. rush, dash — used of flowing water  2. to break forth in or like a sudden flame or flare  3.  a. to appear suddenly an idea ~es into her mind  b. to move with great speed the days ~ by  4.  a. to break forth or out so as to make a sudden display the sun ~ed from behind a cloud  b. to act or speak vehemently and suddenly especially in anger  5.  a. to give off light suddenly or in transient bursts  b. to glow or gleam especially with animation or passion her eyes ~ed with anger  6. to change suddenly or violently into vapor hot water ~ing to steam under reduced pressure  7. to expose one's breasts or genitals usually suddenly and briefly in public  8. to have sudden insight — often used with on  transitive verb  1.  a. archaic splash  b. to fill by a sudden inflow of water  2.  a. to cause the sudden appearance of (light)  b. to cause to burst violently into flame  c.  (1) to cause (light) to reflect  (2) to cause (as a mirror) to reflect light  (3) to cause (a lamp) to ~  d. to convey by means of ~es of light  3.  a. to make known or cause to appear with great speed ~ a message on the screen  b. to display obtrusively and ostentatiously always ~ing a roll of bills  c. to expose to view usually suddenly and briefly ~ed a badge  4. to cover with or form into a thin layer: as  a. to protect against rain by covering with sheet metal or a substitute  b. to coat (as glass) with a thin layer (as of metal or a differently colored glass)  5. to subject (an exposed photographic negative or positive) to a supplementary uniform exposure to light before development in order to modify detail or tone  6. to expose one's breasts or genitals usually suddenly and briefly to ~ed the audience Synonyms:  ~, gleam, glint, sparkle, glitter, glisten, glimmer, shimmer mean to send forth light. ~ implies a sudden and transient outburst of bright light lightning ~ed. gleam suggests a steady light seen through an obscuring medium or against a dark background lights gleamed in the valley. glint implies a cold glancing light glinting steel. sparkle suggests innumerable moving points of bright light the sparkling waters of the gulf. glitter connotes a brilliant sparkling or gleaming glittering diamonds. glisten applies to the soft sparkle from a wet or oily surface glistening rain-drenched sidewalks. glimmer suggests a faint or wavering gleam a distant glimmering light. shimmer implies a soft tremulous gleaming or a blurred reflection a shimmering satin dress.  II. noun  Date: 1549  1.  a. a sudden burst of light  b. a movement of a flag in signaling  2. a sudden and often brilliant burst a ~ of wit  3. a brief time I'll be back in a ~  4.  a. show, display; especially a vulgar ostentatious display  b. archaic a showy ostentatious person  c. one that attracts notice; especially an outstanding athlete  d. pizzazz  5. obsolete thieves' slang  6. something ~ed: as  a. glimpse, look  b. smile  c. a first brief news report  d. ~light 2  e. a quick-spreading flame or momentary intense outburst of radiant heat  f.  (1) ~light 1  (2) a device for producing a ~light for taking photographs  7. rush 7a  8. the rapid conversion of a liquid into vapor  III. adjective  Date: circa 1700  1.  a. ~y, showy  b. of, relating to, or characteristic of ~y people or things ~ behavior  c. of, relating to, or characteristic of persons considered social outcasts ~ language  2. of sudden origin and short duration a ~ fire  IV. adverb  Date: 1970 by very brief exposure to an intense altering agent (as heat or cold) ~ fry ~ freeze