flash, brandish
閃 centers on a sudden, brief burst of light or motion: a flash, or the quick, sweeping action of brandishing something.
閃 combines 門 (gate) with 人 (person), suggesting a person glimpsed through a gate—a fleeting, flashing appearance.
Picture a person 人 darting through a gate 門 so quickly that you only catch a flash of movement. That sudden glimpse is the core of 閃: a flash or a quick brandish.
For セン, imagine a flash of light from a camera's sensor: sensor -> セン, and the flash captures the fleeting moment.
flash (of light); glint
to flash (e.g. lightning); to flicker; to glitter; to sparkle; to gleam
flair; flash
flash (of light); glint
arfvedsonite
(with) a flash of a drawn sword; brandishing a sword
anthophyllite
gedrite
mangano-ferri-eckermannite; kozulite
flash of lightning; flash of a sword; brandishing a sword
green flash (optical phenomenon occurring shortly after sunset or before sunrise)
actinolite
granodiorite
glaucophane
hornblende andesite
amphibolite
hornblende schist
amphibole
tremolite
tremolite