ひらめく・閃くhirameku[3]nakadaka (mid-high)

1. godan verb, intransitive verbto flash (e.g. lightning); to flicker; to glitter; to sparkle; to gleam
2. godan verb, intransitive verbto flutter (e.g. flag); to wave; to undulate
3. godan verb, intransitive verbto flash into one's mind (e.g. an idea); to come to one suddenly
   素晴すばらしい考かんがえがひらめいた。↗

   A wonderful idea just ran through my mind.

• Synonym輝くかがやくNeutralA verb for shining or glowing brightly; it stresses light that stays bright, while 「閃く」 suggests a single flash or a sudden idea.
• Synonym光るひかるNeutralThe most versatile verb for giving off light; it is also used figuratively for talent or ability standing out.
• Synonym光り輝くひかりかがやくNeutralAn emphatic compound for shining brilliantly; it stresses steady brightness and, unlike 「閃く」, does not suggest a momentary flash.
• SynonymキラキラCasualA colloquial mimetic word for glittering and sparkling; it suggests light that keeps sparkling rather than a single flash.
• SynonymきらめくNeutralA verb for glittering and sparkling; it carries a literary flavor and stresses dazzling brilliance.
• Synonymピカピカ光るピカピカひかるCasualA colloquial phrase for bright, repeated flashing; it fits lights and glints off metal, stressing repeated flashing more than 「閃く」.
• SynonymチカチカCasualA colloquial mimetic word for flickering, glaring light; it stresses light that flashes on and off unsteadily.
• RelatedスパークNeutralA loanword for an electric spark, also figuratively a heated clash; 「閃く」 instead covers flashes of light, fluttering flags and sudden ideas.

Use 「閃く」 for a momentary flash or a sudden idea, as in 「稲妻が閃く」 or 「名案が閃く」. For steady light say 「輝く」 or 「光る」; for sparkling, 「煌めく」 or 「キラキラ」; for sparks, 「スパーク」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. きらりと輝かがやく。
2. 旗はたなどが揺れ動ゆれうごく。
3. 瞬間しゅんかん的てきに考かんがえが思い浮おもいうかぶ。