Synonyms for Flash (same or very similar meaning)
WordNet sense 1 (a very short time (as the time it takes the eye blink or the heart to beat)):
heartbeat, instant, jiffy, trice, twinkling, wink, blink of an eye, New York minute, split second
WordNet sense 2 (a short vivid experience):
flashing
WordNet sense 3 (a gaudy outward display):
fanfare, ostentation
WordNet sense 4 (a burst of light used to communicate or illuminate):
flare
WordNet sense 5 (a short news announcement concerning some on-going news story):
newsbreak, newsflash, news bulletin
WordNet sense 6 (a lamp for providing momentary light to take a photograph):
flashbulb, flashgun, photoflash, flash lamp
WordNet sense 7 (tastelessly showy):
brassy, cheap, flashy, garish, gaudy, gimcrack, loud, meretricious, tacky, tawdry, trashy, tatty
WordNet sense 8 (lacking aesthetic or social taste):
tasteless
WordNet sense 9 (gleam or glow intermittently):
blink, twinkle, winkle
WordNet sense 10 (display proudly; act ostentatiously or pretentiously):
flaunt, swank, ostentate
WordNet sense 11 (run or move very quickly or hastily):
dart, dash, scoot, scud, shoot
From the ODE community, based on WordNet
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